(0) Obligation:

Clauses:

mergesort([], []).
mergesort(.(X, []), .(X, [])).
mergesort(.(X, .(Y, L1)), L2) :- ','(split2(.(X, .(Y, L1)), L3, L4), ','(mergesort(L3, L5), ','(mergesort(L4, L6), merge(L5, L6, L2)))).
split(L1, L2, L3) :- split0(L1, L2, L3).
split(L1, L2, L3) :- split1(L1, L2, L3).
split(L1, L2, L3) :- split2(L1, L2, L3).
split0([], [], []).
split1(.(X, []), .(X, []), []).
split2(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) :- split(L1, L2, L3).
merge([], L1, L1).
merge(L1, [], L1).
merge(.(X, L1), .(Y, L2), .(X, L3)) :- ','(le(X, Y), merge(L1, .(Y, L2), L3)).
merge(.(X, L1), .(Y, L2), .(Y, L3)) :- ','(gt(X, Y), merge(.(X, L1), L2, L3)).
gt(s(X), s(Y)) :- gt(X, Y).
gt(s(X), 0).
le(s(X), s(Y)) :- le(X, Y).
le(0, s(Y)).
le(0, 0).

Queries:

mergesort(g,a).

(1) PrologToPiTRSProof (SOUND transformation)

We use the technique of [LOPSTR]. With regard to the inferred argument filtering the predicates were used in the following modes:
mergesort_in: (b,f)
split2_in: (b,f,f)
split_in: (b,f,f)
merge_in: (b,b,f)
le_in: (b,b)
gt_in: (b,b)
Transforming Prolog into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of Prolog

(2) Obligation:

Pi-finite rewrite system:
The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)

(3) DependencyPairsProof (EQUIVALENT transformation)

Using Dependency Pairs [AG00,LOPSTR] we result in the following initial DP problem:
Pi DP problem:
The TRS P consists of the following rules:

MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → SPLIT2_IN_GAA(.(X, .(Y, L1)), L3, L4)
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_GAA(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U5_GAA(L1, L2, L3, split0_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT0_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U6_GAA(L1, L2, L3, split1_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT1_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U7_GAA(L1, L2, L3, split2_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_GA(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_GA(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → MERGE_IN_GGA(L5, L6, L2)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U14_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_GGA(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U13_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_GGA(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x5)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
U8_GAA(x1, x2, x3, x4, x5, x6)  =  U8_GAA(x1, x2, x6)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)
U5_GAA(x1, x2, x3, x4)  =  U5_GAA(x4)
SPLIT0_IN_GAA(x1, x2, x3)  =  SPLIT0_IN_GAA(x1)
U6_GAA(x1, x2, x3, x4)  =  U6_GAA(x4)
SPLIT1_IN_GAA(x1, x2, x3)  =  SPLIT1_IN_GAA(x1)
U7_GAA(x1, x2, x3, x4)  =  U7_GAA(x4)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x5, x6)
U3_GA(x1, x2, x3, x4, x5, x6)  =  U3_GA(x5, x6)
U4_GA(x1, x2, x3, x4, x5)  =  U4_GA(x5)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U14_GG(x1, x2, x3)  =  U14_GG(x3)
U10_GGA(x1, x2, x3, x4, x5, x6)  =  U10_GGA(x1, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U13_GG(x1, x2, x3)  =  U13_GG(x3)
U12_GGA(x1, x2, x3, x4, x5, x6)  =  U12_GGA(x3, x6)

We have to consider all (P,R,Pi)-chains

(4) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → SPLIT2_IN_GAA(.(X, .(Y, L1)), L3, L4)
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_GAA(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U5_GAA(L1, L2, L3, split0_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT0_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U6_GAA(L1, L2, L3, split1_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT1_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U7_GAA(L1, L2, L3, split2_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_GA(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_GA(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → MERGE_IN_GGA(L5, L6, L2)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U14_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_GGA(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U13_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_GGA(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x5)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
U8_GAA(x1, x2, x3, x4, x5, x6)  =  U8_GAA(x1, x2, x6)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)
U5_GAA(x1, x2, x3, x4)  =  U5_GAA(x4)
SPLIT0_IN_GAA(x1, x2, x3)  =  SPLIT0_IN_GAA(x1)
U6_GAA(x1, x2, x3, x4)  =  U6_GAA(x4)
SPLIT1_IN_GAA(x1, x2, x3)  =  SPLIT1_IN_GAA(x1)
U7_GAA(x1, x2, x3, x4)  =  U7_GAA(x4)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x5, x6)
U3_GA(x1, x2, x3, x4, x5, x6)  =  U3_GA(x5, x6)
U4_GA(x1, x2, x3, x4, x5)  =  U4_GA(x5)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U14_GG(x1, x2, x3)  =  U14_GG(x3)
U10_GGA(x1, x2, x3, x4, x5, x6)  =  U10_GGA(x1, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U13_GG(x1, x2, x3)  =  U13_GG(x3)
U12_GGA(x1, x2, x3, x4, x5, x6)  =  U12_GGA(x3, x6)

We have to consider all (P,R,Pi)-chains

(5) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 5 SCCs with 16 less nodes.

(6) Complex Obligation (AND)

(7) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)

We have to consider all (P,R,Pi)-chains

(8) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(9) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains

(10) PiDPToQDPProof (EQUIVALENT transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(11) Obligation:

Q DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(12) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
    The graph contains the following edges 1 > 1, 2 > 2

(13) TRUE

(14) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)

We have to consider all (P,R,Pi)-chains

(15) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(16) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains

(17) PiDPToQDPProof (EQUIVALENT transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(18) Obligation:

Q DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(19) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
    The graph contains the following edges 1 > 1, 2 > 2

(20) TRUE

(21) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(22) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(23) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))

The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(24) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(25) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, le_out_gg) → MERGE_IN_GGA(L1, .(Y, L2))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U14_gg(le_out_gg) → le_out_gg
U13_gg(gt_out_gg) → gt_out_gg

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0)
U13_gg(x0)

We have to consider all (P,Q,R)-chains.

(26) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


U9_GGA(X, L1, Y, L2, le_out_gg) → MERGE_IN_GGA(L1, .(Y, L2))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = x1 + x2   
POL(0) = 1   
POL(MERGE_IN_GGA(x1, x2)) = x1   
POL(U11_GGA(x1, x2, x3, x4, x5)) = x1 + x2   
POL(U13_gg(x1)) = 0   
POL(U14_gg(x1)) = 1   
POL(U9_GGA(x1, x2, x3, x4, x5)) = x2 + x5   
POL(gt_in_gg(x1, x2)) = 0   
POL(gt_out_gg) = 0   
POL(le_in_gg(x1, x2)) = x1   
POL(le_out_gg) = 1   
POL(s(x1)) = 1   

The following usable rules [FROCOS05] were oriented:

le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U14_gg(le_out_gg) → le_out_gg

(27) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U14_gg(le_out_gg) → le_out_gg
U13_gg(gt_out_gg) → gt_out_gg

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0)
U13_gg(x0)

We have to consider all (P,Q,R)-chains.

(28) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(29) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U14_gg(le_out_gg) → le_out_gg
U13_gg(gt_out_gg) → gt_out_gg

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0)
U13_gg(x0)

We have to consider all (P,Q,R)-chains.

(30) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(31) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U13_gg(gt_out_gg) → gt_out_gg

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0)
U13_gg(x0)

We have to consider all (P,Q,R)-chains.

(32) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

le_in_gg(x0, x1)
U14_gg(x0)

(33) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U13_gg(gt_out_gg) → gt_out_gg

The set Q consists of the following terms:

gt_in_gg(x0, x1)
U13_gg(x0)

We have to consider all (P,Q,R)-chains.

(34) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • U11_GGA(X, L1, Y, L2, gt_out_gg) → MERGE_IN_GGA(.(X, L1), L2)
    The graph contains the following edges 4 >= 2

  • MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
    The graph contains the following edges 1 > 1, 1 > 2, 2 > 3, 2 > 4

(35) TRUE

(36) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)

We have to consider all (P,R,Pi)-chains

(37) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(38) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)

R is empty.
The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)

We have to consider all (P,R,Pi)-chains

(39) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(40) Obligation:

Q DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1))) → SPLIT_IN_GAA(L1)
SPLIT_IN_GAA(L1) → SPLIT2_IN_GAA(L1)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(41) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • SPLIT_IN_GAA(L1) → SPLIT2_IN_GAA(L1)
    The graph contains the following edges 1 >= 1

  • SPLIT2_IN_GAA(.(X, .(Y, L1))) → SPLIT_IN_GAA(L1)
    The graph contains the following edges 1 > 1

(42) TRUE

(43) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x3, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x5)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x5, x6)

We have to consider all (P,R,Pi)-chains

(44) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(45) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → U2_GA(L4, mergesort_in_ga(L3))
U2_GA(L4, mergesort_out_ga(L5)) → MERGESORT_IN_GA(L4)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))
U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)

The TRS R consists of the following rules:

mergesort_in_ga([]) → mergesort_out_ga([])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
U1_ga(split2_out_gaa(L3, L4)) → U2_ga(L4, mergesort_in_ga(L3))
U2_ga(L4, mergesort_out_ga(L5)) → U3_ga(L5, mergesort_in_ga(L4))
U3_ga(L5, mergesort_out_ga(L6)) → U4_ga(merge_in_gga(L5, L6))
merge_in_gga([], L1) → merge_out_gga(L1)
merge_in_gga(L1, []) → merge_out_gga(L1)
merge_in_gga(.(X, L1), .(Y, L2)) → U9_gga(X, L1, Y, L2, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U14_gg(le_out_gg) → le_out_gg
U9_gga(X, L1, Y, L2, le_out_gg) → U10_gga(X, merge_in_gga(L1, .(Y, L2)))
merge_in_gga(.(X, L1), .(Y, L2)) → U11_gga(X, L1, Y, L2, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U13_gg(gt_out_gg) → gt_out_gg
U11_gga(X, L1, Y, L2, gt_out_gg) → U12_gga(Y, merge_in_gga(.(X, L1), L2))
U12_gga(Y, merge_out_gga(L3)) → merge_out_gga(.(Y, L3))
U10_gga(X, merge_out_gga(L3)) → merge_out_gga(.(X, L3))
U4_ga(merge_out_gga(L2)) → mergesort_out_ga(L2)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)
U1_ga(x0)
U2_ga(x0, x1)
U3_ga(x0, x1)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1)
U10_gga(x0, x1)
U4_ga(x0)

We have to consider all (P,Q,R)-chains.

(46) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


U1_GA(split2_out_gaa(L3, L4)) → U2_GA(L4, mergesort_in_ga(L3))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO]:

POL(U1_GA(x1)) = 1 +
[0,1]
·x1

POL(split2_out_gaa(x1, x2)) =
/0\
\0/
+
/01\
\11/
·x1 +
/01\
\01/
·x2

POL(U2_GA(x1, x2)) = 0 +
[0,1]
·x1 +
[0,1]
·x2

POL(mergesort_in_ga(x1)) =
/0\
\0/
+
/00\
\11/
·x1

POL(mergesort_out_ga(x1)) =
/0\
\1/
+
/00\
\00/
·x1

POL(MERGESORT_IN_GA(x1)) = 1 +
[0,1]
·x1

POL(.(x1, x2)) =
/0\
\1/
+
/00\
\00/
·x1 +
/00\
\01/
·x2

POL(split2_in_gaa(x1)) =
/0\
\0/
+
/01\
\01/
·x1

POL([]) =
/1\
\0/

POL(U1_ga(x1)) =
/0\
\1/
+
/00\
\00/
·x1

POL(U8_gaa(x1, x2, x3)) =
/1\
\1/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/10\
\10/
·x3

POL(split_in_gaa(x1)) =
/1\
\0/
+
/01\
\00/
·x1

POL(U2_ga(x1, x2)) =
/0\
\1/
+
/00\
\00/
·x1 +
/00\
\00/
·x2

POL(U3_ga(x1, x2)) =
/0\
\1/
+
/00\
\00/
·x1 +
/00\
\00/
·x2

POL(U4_ga(x1)) =
/0\
\1/
+
/00\
\00/
·x1

POL(merge_in_gga(x1, x2)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2

POL(U7_gaa(x1)) =
/1\
\0/
+
/10\
\00/
·x1

POL(split_out_gaa(x1, x2)) =
/1\
\0/
+
/01\
\00/
·x1 +
/01\
\00/
·x2

POL(U5_gaa(x1)) =
/1\
\0/
+
/10\
\00/
·x1

POL(split0_in_gaa(x1)) =
/0\
\1/
+
/00\
\10/
·x1

POL(U6_gaa(x1)) =
/0\
\0/
+
/11\
\00/
·x1

POL(split1_in_gaa(x1)) =
/1\
\0/
+
/00\
\01/
·x1

POL(split0_out_gaa(x1, x2)) =
/0\
\0/
+
/01\
\00/
·x1 +
/01\
\00/
·x2

POL(split1_out_gaa(x1, x2)) =
/0\
\1/
+
/01\
\00/
·x1 +
/00\
\01/
·x2

POL(merge_out_gga(x1)) =
/1\
\0/
+
/00\
\00/
·x1

POL(U9_gga(x1, x2, x3, x4, x5)) =
/0\
\0/
+
/00\
\11/
·x1 +
/01\
\10/
·x2 +
/11\
\11/
·x3 +
/00\
\01/
·x4 +
/00\
\00/
·x5

POL(le_in_gg(x1, x2)) =
/0\
\1/
+
/01\
\00/
·x1 +
/01\
\11/
·x2

POL(U11_gga(x1, x2, x3, x4, x5)) =
/0\
\1/
+
/00\
\00/
·x1 +
/01\
\00/
·x2 +
/01\
\00/
·x3 +
/00\
\10/
·x4 +
/00\
\11/
·x5

POL(gt_in_gg(x1, x2)) =
/0\
\0/
+
/01\
\01/
·x1 +
/00\
\00/
·x2

POL(s(x1)) =
/0\
\0/
+
/10\
\00/
·x1

POL(U14_gg(x1)) =
/0\
\1/
+
/11\
\11/
·x1

POL(0) =
/0\
\0/

POL(le_out_gg) =
/0\
\0/

POL(U10_gga(x1, x2)) =
/1\
\1/
+
/00\
\00/
·x1 +
/00\
\10/
·x2

POL(U13_gg(x1)) =
/1\
\0/
+
/10\
\00/
·x1

POL(gt_out_gg) =
/0\
\1/

POL(U12_gga(x1, x2)) =
/0\
\1/
+
/10\
\01/
·x1 +
/00\
\00/
·x2

The following usable rules [FROCOS05] were oriented:

mergesort_in_ga([]) → mergesort_out_ga([])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
U1_ga(split2_out_gaa(L3, L4)) → U2_ga(L4, mergesort_in_ga(L3))
U2_ga(L4, mergesort_out_ga(L5)) → U3_ga(L5, mergesort_in_ga(L4))
U3_ga(L5, mergesort_out_ga(L6)) → U4_ga(merge_in_gga(L5, L6))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
U4_ga(merge_out_gga(L2)) → mergesort_out_ga(L2)

(47) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U2_GA(L4, mergesort_out_ga(L5)) → MERGESORT_IN_GA(L4)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))
U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)

The TRS R consists of the following rules:

mergesort_in_ga([]) → mergesort_out_ga([])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
U1_ga(split2_out_gaa(L3, L4)) → U2_ga(L4, mergesort_in_ga(L3))
U2_ga(L4, mergesort_out_ga(L5)) → U3_ga(L5, mergesort_in_ga(L4))
U3_ga(L5, mergesort_out_ga(L6)) → U4_ga(merge_in_gga(L5, L6))
merge_in_gga([], L1) → merge_out_gga(L1)
merge_in_gga(L1, []) → merge_out_gga(L1)
merge_in_gga(.(X, L1), .(Y, L2)) → U9_gga(X, L1, Y, L2, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U14_gg(le_out_gg) → le_out_gg
U9_gga(X, L1, Y, L2, le_out_gg) → U10_gga(X, merge_in_gga(L1, .(Y, L2)))
merge_in_gga(.(X, L1), .(Y, L2)) → U11_gga(X, L1, Y, L2, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U13_gg(gt_out_gg) → gt_out_gg
U11_gga(X, L1, Y, L2, gt_out_gg) → U12_gga(Y, merge_in_gga(.(X, L1), L2))
U12_gga(Y, merge_out_gga(L3)) → merge_out_gga(.(Y, L3))
U10_gga(X, merge_out_gga(L3)) → merge_out_gga(.(X, L3))
U4_ga(merge_out_gga(L2)) → mergesort_out_ga(L2)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)
U1_ga(x0)
U2_ga(x0, x1)
U3_ga(x0, x1)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1)
U10_gga(x0, x1)
U4_ga(x0)

We have to consider all (P,Q,R)-chains.

(48) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(49) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

mergesort_in_ga([]) → mergesort_out_ga([])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
U1_ga(split2_out_gaa(L3, L4)) → U2_ga(L4, mergesort_in_ga(L3))
U2_ga(L4, mergesort_out_ga(L5)) → U3_ga(L5, mergesort_in_ga(L4))
U3_ga(L5, mergesort_out_ga(L6)) → U4_ga(merge_in_gga(L5, L6))
merge_in_gga([], L1) → merge_out_gga(L1)
merge_in_gga(L1, []) → merge_out_gga(L1)
merge_in_gga(.(X, L1), .(Y, L2)) → U9_gga(X, L1, Y, L2, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U14_gg(le_out_gg) → le_out_gg
U9_gga(X, L1, Y, L2, le_out_gg) → U10_gga(X, merge_in_gga(L1, .(Y, L2)))
merge_in_gga(.(X, L1), .(Y, L2)) → U11_gga(X, L1, Y, L2, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg
U13_gg(gt_out_gg) → gt_out_gg
U11_gga(X, L1, Y, L2, gt_out_gg) → U12_gga(Y, merge_in_gga(.(X, L1), L2))
U12_gga(Y, merge_out_gga(L3)) → merge_out_gga(.(Y, L3))
U10_gga(X, merge_out_gga(L3)) → merge_out_gga(.(X, L3))
U4_ga(merge_out_gga(L2)) → mergesort_out_ga(L2)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)
U1_ga(x0)
U2_ga(x0, x1)
U3_ga(x0, x1)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1)
U10_gga(x0, x1)
U4_ga(x0)

We have to consider all (P,Q,R)-chains.

(50) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(51) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)
U1_ga(x0)
U2_ga(x0, x1)
U3_ga(x0, x1)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1)
U10_gga(x0, x1)
U4_ga(x0)

We have to consider all (P,Q,R)-chains.

(52) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

mergesort_in_ga(x0)
U1_ga(x0)
U2_ga(x0, x1)
U3_ga(x0, x1)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1)
U10_gga(x0, x1)
U4_ga(x0)

(53) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split0_in_gaa([]) → split0_out_gaa([], [])
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(54) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.

Strictly oriented rules of the TRS R:

U7_gaa(split2_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
split0_in_gaa([]) → split0_out_gaa([], [])

Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 2 + x1 + 2·x2   
POL(MERGESORT_IN_GA(x1)) = 2·x1   
POL(U1_GA(x1)) = 2·x1   
POL(U5_gaa(x1)) = x1   
POL(U6_gaa(x1)) = 1 + x1   
POL(U7_gaa(x1)) = 2 + x1   
POL(U8_gaa(x1, x2, x3)) = 2 + x1 + x2 + 2·x3   
POL([]) = 1   
POL(split0_in_gaa(x1)) = 2 + 2·x1   
POL(split0_out_gaa(x1, x2)) = 1 + x1 + x2   
POL(split1_in_gaa(x1)) = 1 + 2·x1   
POL(split1_out_gaa(x1, x2)) = 2·x1 + x2   
POL(split2_in_gaa(x1)) = x1   
POL(split2_out_gaa(x1, x2)) = x1 + x2   
POL(split_in_gaa(x1)) = 2 + 2·x1   
POL(split_out_gaa(x1, x2)) = 1 + x1 + x2   

(55) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)
U5_gaa(split0_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(56) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(57) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(58) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.

Strictly oriented rules of the TRS R:

split_in_gaa(L1) → U5_gaa(split0_in_gaa(L1))
split_in_gaa(L1) → U7_gaa(split2_in_gaa(L1))

Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 1 + x1 + x2   
POL(MERGESORT_IN_GA(x1)) = x1   
POL(U1_GA(x1)) = x1   
POL(U5_gaa(x1)) = x1   
POL(U6_gaa(x1)) = x1   
POL(U7_gaa(x1)) = x1   
POL(U8_gaa(x1, x2, x3)) = 1 + x1 + x2 + x3   
POL([]) = 0   
POL(split0_in_gaa(x1)) = x1   
POL(split1_in_gaa(x1)) = 1 + x1   
POL(split1_out_gaa(x1, x2)) = 1 + x1 + x2   
POL(split2_in_gaa(x1)) = x1   
POL(split2_out_gaa(x1, x2)) = x1 + x2   
POL(split_in_gaa(x1)) = 1 + x1   
POL(split_out_gaa(x1, x2)) = 1 + x1 + x2   

(59) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U7_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(60) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

split0_in_gaa(x0)
U5_gaa(x0)
U7_gaa(x0)

(61) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(62) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

U1_GA(split2_out_gaa(L3, L4)) → MERGESORT_IN_GA(L3)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(split2_in_gaa(.(X, .(Y, L1))))

Strictly oriented rules of the TRS R:

U8_gaa(X, Y, split_out_gaa(L2, L3)) → split2_out_gaa(.(X, L2), .(Y, L3))

Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = x1 + 2·x2   
POL(MERGESORT_IN_GA(x1)) = 1 + 2·x1   
POL(U1_GA(x1)) = 2·x1   
POL(U6_gaa(x1)) = x1   
POL(U8_gaa(x1, x2, x3)) = x1 + 2·x2 + 2·x3   
POL([]) = 2   
POL(split1_in_gaa(x1)) = 2·x1   
POL(split1_out_gaa(x1, x2)) = 2 + x1 + x2   
POL(split2_in_gaa(x1)) = x1   
POL(split2_out_gaa(x1, x2)) = 1 + x1 + x2   
POL(split_in_gaa(x1)) = 2·x1   
POL(split_out_gaa(x1, x2)) = 2 + x1 + x2   

(63) Obligation:

Q DP problem:
P is empty.
The TRS R consists of the following rules:

split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, split_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), [])
U6_gaa(split1_out_gaa(L2, L3)) → split_out_gaa(L2, L3)

The set Q consists of the following terms:

split2_in_gaa(x0)
split_in_gaa(x0)
split1_in_gaa(x0)
U6_gaa(x0)
U8_gaa(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(64) PisEmptyProof (EQUIVALENT transformation)

The TRS P is empty. Hence, there is no (P,Q,R) chain.

(65) TRUE

(66) PrologToPiTRSProof (SOUND transformation)

We use the technique of [LOPSTR]. With regard to the inferred argument filtering the predicates were used in the following modes:
mergesort_in: (b,f)
split2_in: (b,f,f)
split_in: (b,f,f)
merge_in: (b,b,f)
le_in: (b,b)
gt_in: (b,b)
Transforming Prolog into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of Prolog

(67) Obligation:

Pi-finite rewrite system:
The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)

(68) DependencyPairsProof (EQUIVALENT transformation)

Using Dependency Pairs [AG00,LOPSTR] we result in the following initial DP problem:
Pi DP problem:
The TRS P consists of the following rules:

MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → SPLIT2_IN_GAA(.(X, .(Y, L1)), L3, L4)
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_GAA(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U5_GAA(L1, L2, L3, split0_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT0_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U6_GAA(L1, L2, L3, split1_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT1_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U7_GAA(L1, L2, L3, split2_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_GA(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_GA(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → MERGE_IN_GGA(L5, L6, L2)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U14_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_GGA(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U13_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_GGA(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x1, x2, x3, x5)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
U8_GAA(x1, x2, x3, x4, x5, x6)  =  U8_GAA(x1, x2, x3, x6)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)
U5_GAA(x1, x2, x3, x4)  =  U5_GAA(x1, x4)
SPLIT0_IN_GAA(x1, x2, x3)  =  SPLIT0_IN_GAA(x1)
U6_GAA(x1, x2, x3, x4)  =  U6_GAA(x1, x4)
SPLIT1_IN_GAA(x1, x2, x3)  =  SPLIT1_IN_GAA(x1)
U7_GAA(x1, x2, x3, x4)  =  U7_GAA(x1, x4)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x1, x2, x3, x5, x6)
U3_GA(x1, x2, x3, x4, x5, x6)  =  U3_GA(x1, x2, x3, x5, x6)
U4_GA(x1, x2, x3, x4, x5)  =  U4_GA(x1, x2, x3, x5)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U14_GG(x1, x2, x3)  =  U14_GG(x1, x2, x3)
U10_GGA(x1, x2, x3, x4, x5, x6)  =  U10_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U13_GG(x1, x2, x3)  =  U13_GG(x1, x2, x3)
U12_GGA(x1, x2, x3, x4, x5, x6)  =  U12_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(69) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → SPLIT2_IN_GAA(.(X, .(Y, L1)), L3, L4)
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_GAA(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U5_GAA(L1, L2, L3, split0_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT0_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U6_GAA(L1, L2, L3, split1_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT1_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → U7_GAA(L1, L2, L3, split2_in_gaa(L1, L2, L3))
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_GA(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_GA(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
U3_GA(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → MERGE_IN_GGA(L5, L6, L2)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U14_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_GGA(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U13_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_GGA(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x1, x2, x3, x5)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
U8_GAA(x1, x2, x3, x4, x5, x6)  =  U8_GAA(x1, x2, x3, x6)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)
U5_GAA(x1, x2, x3, x4)  =  U5_GAA(x1, x4)
SPLIT0_IN_GAA(x1, x2, x3)  =  SPLIT0_IN_GAA(x1)
U6_GAA(x1, x2, x3, x4)  =  U6_GAA(x1, x4)
SPLIT1_IN_GAA(x1, x2, x3)  =  SPLIT1_IN_GAA(x1)
U7_GAA(x1, x2, x3, x4)  =  U7_GAA(x1, x4)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x1, x2, x3, x5, x6)
U3_GA(x1, x2, x3, x4, x5, x6)  =  U3_GA(x1, x2, x3, x5, x6)
U4_GA(x1, x2, x3, x4, x5)  =  U4_GA(x1, x2, x3, x5)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U14_GG(x1, x2, x3)  =  U14_GG(x1, x2, x3)
U10_GGA(x1, x2, x3, x4, x5, x6)  =  U10_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U13_GG(x1, x2, x3)  =  U13_GG(x1, x2, x3)
U12_GGA(x1, x2, x3, x4, x5, x6)  =  U12_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(70) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 5 SCCs with 16 less nodes.

(71) Complex Obligation (AND)

(72) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)

We have to consider all (P,R,Pi)-chains

(73) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(74) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains

(75) PiDPToQDPProof (EQUIVALENT transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(76) Obligation:

Q DP problem:
The TRS P consists of the following rules:

GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(77) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
    The graph contains the following edges 1 > 1, 2 > 2

(78) TRUE

(79) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)

We have to consider all (P,R,Pi)-chains

(80) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(81) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains

(82) PiDPToQDPProof (EQUIVALENT transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(83) Obligation:

Q DP problem:
The TRS P consists of the following rules:

LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(84) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
    The graph contains the following edges 1 > 1, 2 > 2

(85) TRUE

(86) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(87) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(88) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, L3, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2), L3)
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(X, L3)) → U9_GGA(X, L1, Y, L2, L3, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2), .(Y, L3)) → U11_GGA(X, L1, Y, L2, L3, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2, L3)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))

The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
MERGE_IN_GGA(x1, x2, x3)  =  MERGE_IN_GGA(x1, x2)
U9_GGA(x1, x2, x3, x4, x5, x6)  =  U9_GGA(x1, x2, x3, x4, x6)
U11_GGA(x1, x2, x3, x4, x5, x6)  =  U11_GGA(x1, x2, x3, x4, x6)

We have to consider all (P,R,Pi)-chains

(89) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(90) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))
U11_GGA(X, L1, Y, L2, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U13_gg(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(91) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

U11_GGA(X, L1, Y, L2, gt_out_gg(X, Y)) → MERGE_IN_GGA(.(X, L1), L2)

Strictly oriented rules of the TRS R:

gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)

Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 2·x1 + x2   
POL(0) = 2   
POL(MERGE_IN_GGA(x1, x2)) = 2·x1 + 2·x2   
POL(U11_GGA(x1, x2, x3, x4, x5)) = 2·x1 + 2·x2 + 2·x3 + 2·x4 + x5   
POL(U13_gg(x1, x2, x3)) = 2·x1 + 2·x2 + x3   
POL(U14_gg(x1, x2, x3)) = x1 + x2 + x3   
POL(U9_GGA(x1, x2, x3, x4, x5)) = x1 + 2·x2 + 2·x3 + 2·x4 + 2·x5   
POL(gt_in_gg(x1, x2)) = 2·x1 + 2·x2   
POL(gt_out_gg(x1, x2)) = 1 + 2·x1 + x2   
POL(le_in_gg(x1, x2)) = x1 + x2   
POL(le_out_gg(x1, x2)) = x1 + x2   
POL(s(x1)) = 2·x1   

(92) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U11_GGA(X, L1, Y, L2, gt_in_gg(X, Y))

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U13_gg(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(93) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(94) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U13_gg(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(95) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(96) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))

The set Q consists of the following terms:

le_in_gg(x0, x1)
gt_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U13_gg(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(97) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

gt_in_gg(x0, x1)
U13_gg(x0, x1, x2)

(98) Obligation:

Q DP problem:
The TRS P consists of the following rules:

MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))

The set Q consists of the following terms:

le_in_gg(x0, x1)
U14_gg(x0, x1, x2)

We have to consider all (P,Q,R)-chains.

(99) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • U9_GGA(X, L1, Y, L2, le_out_gg(X, Y)) → MERGE_IN_GGA(L1, .(Y, L2))
    The graph contains the following edges 2 >= 1

  • MERGE_IN_GGA(.(X, L1), .(Y, L2)) → U9_GGA(X, L1, Y, L2, le_in_gg(X, Y))
    The graph contains the following edges 1 > 1, 1 > 2, 2 > 3, 2 > 4

(100) TRUE

(101) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)

We have to consider all (P,R,Pi)-chains

(102) UsableRulesProof (EQUIVALENT transformation)

For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.

(103) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → SPLIT_IN_GAA(L1, L2, L3)
SPLIT_IN_GAA(L1, L2, L3) → SPLIT2_IN_GAA(L1, L2, L3)

R is empty.
The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
SPLIT2_IN_GAA(x1, x2, x3)  =  SPLIT2_IN_GAA(x1)
SPLIT_IN_GAA(x1, x2, x3)  =  SPLIT_IN_GAA(x1)

We have to consider all (P,R,Pi)-chains

(104) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(105) Obligation:

Q DP problem:
The TRS P consists of the following rules:

SPLIT2_IN_GAA(.(X, .(Y, L1))) → SPLIT_IN_GAA(L1)
SPLIT_IN_GAA(L1) → SPLIT2_IN_GAA(L1)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.

(106) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:

  • SPLIT_IN_GAA(L1) → SPLIT2_IN_GAA(L1)
    The graph contains the following edges 1 >= 1

  • SPLIT2_IN_GAA(.(X, .(Y, L1))) → SPLIT_IN_GAA(L1)
    The graph contains the following edges 1 > 1

(107) TRUE

(108) Obligation:

Pi DP problem:
The TRS P consists of the following rules:

U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_GA(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4, L6)
MERGESORT_IN_GA(.(X, .(Y, L1)), L2) → U1_GA(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
U1_GA(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3, L5)

The TRS R consists of the following rules:

mergesort_in_ga([], []) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, []), .(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1)), L2) → U1_ga(X, Y, L1, L2, split2_in_gaa(.(X, .(Y, L1)), L3, L4))
split2_in_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3)) → U8_gaa(X, Y, L1, L2, L3, split_in_gaa(L1, L2, L3))
split_in_gaa(L1, L2, L3) → U5_gaa(L1, L2, L3, split0_in_gaa(L1, L2, L3))
split0_in_gaa([], [], []) → split0_out_gaa([], [], [])
U5_gaa(L1, L2, L3, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U6_gaa(L1, L2, L3, split1_in_gaa(L1, L2, L3))
split1_in_gaa(.(X, []), .(X, []), []) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, L2, L3, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1, L2, L3) → U7_gaa(L1, L2, L3, split2_in_gaa(L1, L2, L3))
U7_gaa(L1, L2, L3, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, L2, L3, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, L2, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L2, L4, mergesort_in_ga(L3, L5))
U2_ga(X, Y, L1, L2, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L2, L5, mergesort_in_ga(L4, L6))
U3_ga(X, Y, L1, L2, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, L2, merge_in_gga(L5, L6, L2))
merge_in_gga([], L1, L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, [], L1) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2), .(X, L3)) → U9_gga(X, L1, Y, L2, L3, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, L3, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, L3, merge_in_gga(L1, .(Y, L2), L3))
merge_in_gga(.(X, L1), .(Y, L2), .(Y, L3)) → U11_gga(X, L1, Y, L2, L3, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, L3, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, L3, merge_in_gga(.(X, L1), L2, L3))
U12_gga(X, L1, Y, L2, L3, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, L3, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, L2, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The argument filtering Pi contains the following mapping:
mergesort_in_ga(x1, x2)  =  mergesort_in_ga(x1)
[]  =  []
mergesort_out_ga(x1, x2)  =  mergesort_out_ga(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_ga(x1, x2, x3, x4, x5)  =  U1_ga(x1, x2, x3, x5)
split2_in_gaa(x1, x2, x3)  =  split2_in_gaa(x1)
U8_gaa(x1, x2, x3, x4, x5, x6)  =  U8_gaa(x1, x2, x3, x6)
split_in_gaa(x1, x2, x3)  =  split_in_gaa(x1)
U5_gaa(x1, x2, x3, x4)  =  U5_gaa(x1, x4)
split0_in_gaa(x1, x2, x3)  =  split0_in_gaa(x1)
split0_out_gaa(x1, x2, x3)  =  split0_out_gaa(x1, x2, x3)
split_out_gaa(x1, x2, x3)  =  split_out_gaa(x1, x2, x3)
U6_gaa(x1, x2, x3, x4)  =  U6_gaa(x1, x4)
split1_in_gaa(x1, x2, x3)  =  split1_in_gaa(x1)
split1_out_gaa(x1, x2, x3)  =  split1_out_gaa(x1, x2, x3)
U7_gaa(x1, x2, x3, x4)  =  U7_gaa(x1, x4)
split2_out_gaa(x1, x2, x3)  =  split2_out_gaa(x1, x2, x3)
U2_ga(x1, x2, x3, x4, x5, x6)  =  U2_ga(x1, x2, x3, x5, x6)
U3_ga(x1, x2, x3, x4, x5, x6)  =  U3_ga(x1, x2, x3, x5, x6)
U4_ga(x1, x2, x3, x4, x5)  =  U4_ga(x1, x2, x3, x5)
merge_in_gga(x1, x2, x3)  =  merge_in_gga(x1, x2)
merge_out_gga(x1, x2, x3)  =  merge_out_gga(x1, x2, x3)
U9_gga(x1, x2, x3, x4, x5, x6)  =  U9_gga(x1, x2, x3, x4, x6)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U14_gg(x1, x2, x3)  =  U14_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U10_gga(x1, x2, x3, x4, x5, x6)  =  U10_gga(x1, x2, x3, x4, x6)
U11_gga(x1, x2, x3, x4, x5, x6)  =  U11_gga(x1, x2, x3, x4, x6)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U13_gg(x1, x2, x3)  =  U13_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U12_gga(x1, x2, x3, x4, x5, x6)  =  U12_gga(x1, x2, x3, x4, x6)
MERGESORT_IN_GA(x1, x2)  =  MERGESORT_IN_GA(x1)
U1_GA(x1, x2, x3, x4, x5)  =  U1_GA(x1, x2, x3, x5)
U2_GA(x1, x2, x3, x4, x5, x6)  =  U2_GA(x1, x2, x3, x5, x6)

We have to consider all (P,R,Pi)-chains

(109) PiDPToQDPProof (SOUND transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(110) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L4, mergesort_in_ga(L3))
U2_GA(X, Y, L1, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(X, Y, L1, split2_in_gaa(.(X, .(Y, L1))))
U1_GA(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3)

The TRS R consists of the following rules:

mergesort_in_ga([]) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(X, Y, L1, split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, L1, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(L1, split0_in_gaa(L1))
split0_in_gaa([]) → split0_out_gaa([], [], [])
U5_gaa(L1, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1) → U6_gaa(L1, split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1) → U7_gaa(L1, split2_in_gaa(L1))
U7_gaa(L1, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L4, mergesort_in_ga(L3))
U2_ga(X, Y, L1, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L5, mergesort_in_ga(L4))
U3_ga(X, Y, L1, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, merge_in_gga(L5, L6))
merge_in_gga([], L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, []) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2)) → U9_gga(X, L1, Y, L2, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, merge_in_gga(L1, .(Y, L2)))
merge_in_gga(.(X, L1), .(Y, L2)) → U11_gga(X, L1, Y, L2, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, merge_in_gga(.(X, L1), L2))
U12_gga(X, L1, Y, L2, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0, x1)
split1_in_gaa(x0)
U6_gaa(x0, x1)
U7_gaa(x0, x1)
U8_gaa(x0, x1, x2, x3)
U1_ga(x0, x1, x2, x3)
U2_ga(x0, x1, x2, x3, x4)
U3_ga(x0, x1, x2, x3, x4)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0, x1, x2)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1, x2, x3, x4)
U10_gga(x0, x1, x2, x3, x4)
U4_ga(x0, x1, x2, x3)

We have to consider all (P,Q,R)-chains.

(111) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


U1_GA(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → MERGESORT_IN_GA(L3)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO]:

POL(U1_GA(x1, x2, x3, x4)) = 0 +
[0,0]
·x1 +
[0,0]
·x2 +
[0,0]
·x3 +
[1,0]
·x4

POL(split2_out_gaa(x1, x2, x3)) =
/1\
\0/
+
/10\
\00/
·x1 +
/01\
\11/
·x2 +
/01\
\11/
·x3

POL(.(x1, x2)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\11/
·x2

POL(U2_GA(x1, x2, x3, x4, x5)) = 0 +
[0,0]
·x1 +
[0,0]
·x2 +
[0,0]
·x3 +
[0,1]
·x4 +
[1,1]
·x5

POL(mergesort_in_ga(x1)) =
/1\
\1/
+
/01\
\00/
·x1

POL(mergesort_out_ga(x1, x2)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2

POL(MERGESORT_IN_GA(x1)) = 1 +
[0,1]
·x1

POL(split2_in_gaa(x1)) =
/1\
\0/
+
/01\
\11/
·x1

POL([]) =
/0\
\0/

POL(U1_ga(x1, x2, x3, x4)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3 +
/10\
\00/
·x4

POL(U8_gaa(x1, x2, x3, x4)) =
/1\
\1/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3 +
/11\
\11/
·x4

POL(split_in_gaa(x1)) =
/1\
\0/
+
/00\
\11/
·x1

POL(U2_ga(x1, x2, x3, x4, x5)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3 +
/01\
\00/
·x4 +
/11\
\00/
·x5

POL(U3_ga(x1, x2, x3, x4, x5)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3 +
/00\
\00/
·x4 +
/00\
\00/
·x5

POL(U4_ga(x1, x2, x3, x4)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3 +
/00\
\00/
·x4

POL(merge_in_gga(x1, x2)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2

POL(U7_gaa(x1, x2)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\01/
·x2

POL(split_out_gaa(x1, x2, x3)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\11/
·x2 +
/00\
\11/
·x3

POL(U5_gaa(x1, x2)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\11/
·x2

POL(split0_in_gaa(x1)) =
/0\
\0/
+
/00\
\00/
·x1

POL(U6_gaa(x1, x2)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\10/
·x2

POL(split1_in_gaa(x1)) =
/0\
\1/
+
/10\
\00/
·x1

POL(split0_out_gaa(x1, x2, x3)) =
/0\
\0/
+
/01\
\01/
·x1 +
/01\
\10/
·x2 +
/10\
\01/
·x3

POL(split1_out_gaa(x1, x2, x3)) =
/0\
\0/
+
/01\
\00/
·x1 +
/11\
\00/
·x2 +
/11\
\00/
·x3

POL(merge_out_gga(x1, x2, x3)) =
/1\
\1/
+
/01\
\00/
·x1 +
/00\
\11/
·x2 +
/11\
\00/
·x3

POL(U9_gga(x1, x2, x3, x4, x5)) =
/0\
\0/
+
/00\
\00/
·x1 +
/11\
\01/
·x2 +
/00\
\00/
·x3 +
/00\
\10/
·x4 +
/00\
\00/
·x5

POL(le_in_gg(x1, x2)) =
/0\
\1/
+
/00\
\11/
·x1 +
/00\
\00/
·x2

POL(U11_gga(x1, x2, x3, x4, x5)) =
/1\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\10/
·x3 +
/00\
\01/
·x4 +
/00\
\00/
·x5

POL(gt_in_gg(x1, x2)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\01/
·x2

POL(s(x1)) =
/0\
\0/
+
/11\
\11/
·x1

POL(U14_gg(x1, x2, x3)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\10/
·x2 +
/01\
\00/
·x3

POL(0) =
/1\
\0/

POL(le_out_gg(x1, x2)) =
/0\
\0/
+
/00\
\11/
·x1 +
/10\
\00/
·x2

POL(U10_gga(x1, x2, x3, x4, x5)) =
/0\
\1/
+
/10\
\11/
·x1 +
/01\
\00/
·x2 +
/01\
\00/
·x3 +
/01\
\00/
·x4 +
/00\
\00/
·x5

POL(U13_gg(x1, x2, x3)) =
/0\
\0/
+
/00\
\11/
·x1 +
/01\
\00/
·x2 +
/01\
\10/
·x3

POL(gt_out_gg(x1, x2)) =
/0\
\0/
+
/11\
\00/
·x1 +
/00\
\11/
·x2

POL(U12_gga(x1, x2, x3, x4, x5)) =
/1\
\0/
+
/00\
\10/
·x1 +
/01\
\10/
·x2 +
/01\
\00/
·x3 +
/01\
\00/
·x4 +
/00\
\00/
·x5

The following usable rules [FROCOS05] were oriented:

mergesort_in_ga([]) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(X, Y, L1, split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, L1, split_in_gaa(L1))
U1_ga(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L4, mergesort_in_ga(L3))
U2_ga(X, Y, L1, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L5, mergesort_in_ga(L4))
U3_ga(X, Y, L1, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, merge_in_gga(L5, L6))
split_in_gaa(L1) → U7_gaa(L1, split2_in_gaa(L1))
U7_gaa(L1, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1) → U5_gaa(L1, split0_in_gaa(L1))
split_in_gaa(L1) → U6_gaa(L1, split1_in_gaa(L1))
U8_gaa(X, Y, L1, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
split0_in_gaa([]) → split0_out_gaa([], [], [])
U5_gaa(L1, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U4_ga(X, Y, L1, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

(112) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U1_GA(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_GA(X, Y, L1, L4, mergesort_in_ga(L3))
U2_GA(X, Y, L1, L4, mergesort_out_ga(L3, L5)) → MERGESORT_IN_GA(L4)
MERGESORT_IN_GA(.(X, .(Y, L1))) → U1_GA(X, Y, L1, split2_in_gaa(.(X, .(Y, L1))))

The TRS R consists of the following rules:

mergesort_in_ga([]) → mergesort_out_ga([], [])
mergesort_in_ga(.(X, [])) → mergesort_out_ga(.(X, []), .(X, []))
mergesort_in_ga(.(X, .(Y, L1))) → U1_ga(X, Y, L1, split2_in_gaa(.(X, .(Y, L1))))
split2_in_gaa(.(X, .(Y, L1))) → U8_gaa(X, Y, L1, split_in_gaa(L1))
split_in_gaa(L1) → U5_gaa(L1, split0_in_gaa(L1))
split0_in_gaa([]) → split0_out_gaa([], [], [])
U5_gaa(L1, split0_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1) → U6_gaa(L1, split1_in_gaa(L1))
split1_in_gaa(.(X, [])) → split1_out_gaa(.(X, []), .(X, []), [])
U6_gaa(L1, split1_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
split_in_gaa(L1) → U7_gaa(L1, split2_in_gaa(L1))
U7_gaa(L1, split2_out_gaa(L1, L2, L3)) → split_out_gaa(L1, L2, L3)
U8_gaa(X, Y, L1, split_out_gaa(L1, L2, L3)) → split2_out_gaa(.(X, .(Y, L1)), .(X, L2), .(Y, L3))
U1_ga(X, Y, L1, split2_out_gaa(.(X, .(Y, L1)), L3, L4)) → U2_ga(X, Y, L1, L4, mergesort_in_ga(L3))
U2_ga(X, Y, L1, L4, mergesort_out_ga(L3, L5)) → U3_ga(X, Y, L1, L5, mergesort_in_ga(L4))
U3_ga(X, Y, L1, L5, mergesort_out_ga(L4, L6)) → U4_ga(X, Y, L1, merge_in_gga(L5, L6))
merge_in_gga([], L1) → merge_out_gga([], L1, L1)
merge_in_gga(L1, []) → merge_out_gga(L1, [], L1)
merge_in_gga(.(X, L1), .(Y, L2)) → U9_gga(X, L1, Y, L2, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U14_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(Y)) → le_out_gg(0, s(Y))
le_in_gg(0, 0) → le_out_gg(0, 0)
U14_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U9_gga(X, L1, Y, L2, le_out_gg(X, Y)) → U10_gga(X, L1, Y, L2, merge_in_gga(L1, .(Y, L2)))
merge_in_gga(.(X, L1), .(Y, L2)) → U11_gga(X, L1, Y, L2, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U13_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(X), 0) → gt_out_gg(s(X), 0)
U13_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U11_gga(X, L1, Y, L2, gt_out_gg(X, Y)) → U12_gga(X, L1, Y, L2, merge_in_gga(.(X, L1), L2))
U12_gga(X, L1, Y, L2, merge_out_gga(.(X, L1), L2, L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(Y, L3))
U10_gga(X, L1, Y, L2, merge_out_gga(L1, .(Y, L2), L3)) → merge_out_gga(.(X, L1), .(Y, L2), .(X, L3))
U4_ga(X, Y, L1, merge_out_gga(L5, L6, L2)) → mergesort_out_ga(.(X, .(Y, L1)), L2)

The set Q consists of the following terms:

mergesort_in_ga(x0)
split2_in_gaa(x0)
split_in_gaa(x0)
split0_in_gaa(x0)
U5_gaa(x0, x1)
split1_in_gaa(x0)
U6_gaa(x0, x1)
U7_gaa(x0, x1)
U8_gaa(x0, x1, x2, x3)
U1_ga(x0, x1, x2, x3)
U2_ga(x0, x1, x2, x3, x4)
U3_ga(x0, x1, x2, x3, x4)
merge_in_gga(x0, x1)
le_in_gg(x0, x1)
U14_gg(x0, x1, x2)
U9_gga(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U13_gg(x0, x1, x2)
U11_gga(x0, x1, x2, x3, x4)
U12_gga(x0, x1, x2, x3, x4)
U10_gga(x0, x1, x2, x3, x4)
U4_ga(x0, x1, x2, x3)

We have to consider all (P,Q,R)-chains.