(0) Obligation:

Clauses:

mergesort([], [], Ls).
mergesort(.(X, []), .(X, []), Ls).
mergesort(.(X, .(Y, Xs)), Ys, .(H, Ls)) :- ','(split(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)), ','(mergesort(X1s, Y1s, Ls), ','(mergesort(X2s, Y2s, Ls), merge(Y1s, Y2s, Ys, .(H, Ls))))).
split([], [], [], Ls).
split(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) :- split(Xs, Zs, Ys, Ls).
merge([], Xs, Xs, Ls).
merge(Xs, [], Xs, Ls).
merge(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) :- ','(le(X, Y), merge(Xs, .(Y, Ys), Zs, Ls)).
merge(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) :- ','(gt(X, Y), merge(.(X, Xs), Ys, Zs, Ls)).
gt(s(X), s(Y)) :- gt(X, Y).
gt(s(0), 0).
le(s(X), s(Y)) :- le(X, Y).
le(0, s(0)).
le(0, 0).

Queries:

mergesort(g,a,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,f)
split_in: (b,f,f,f)
merge_in: (b,b,f,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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)

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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)

(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_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → SPLIT_IN_GAAA(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_GAAA(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_GAA(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → MERGE_IN_GGAA(Y1s, Y2s, Ys, .(H, Ls))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U11_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U10_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x1, x2, x3, x7)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)
U5_GAAA(x1, x2, x3, x4, x5, x6, x7)  =  U5_GAAA(x1, x2, x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x1, x2, x3, x7, x8)
U3_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_GAA(x1, x2, x3, x7, x8)
U4_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U4_GAA(x1, x2, x3, x7)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U11_GG(x1, x2, x3)  =  U11_GG(x1, x2, x3)
U7_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U10_GG(x1, x2, x3)  =  U10_GG(x1, x2, x3)
U9_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_GGAA(x1, x2, x3, x4, x8)

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

(4) Obligation:

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

MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → SPLIT_IN_GAAA(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_GAAA(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_GAA(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → MERGE_IN_GGAA(Y1s, Y2s, Ys, .(H, Ls))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U11_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U10_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x1, x2, x3, x7)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)
U5_GAAA(x1, x2, x3, x4, x5, x6, x7)  =  U5_GAAA(x1, x2, x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x1, x2, x3, x7, x8)
U3_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_GAA(x1, x2, x3, x7, x8)
U4_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U4_GAA(x1, x2, x3, x7)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U11_GG(x1, x2, x3)  =  U11_GG(x1, x2, x3)
U7_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U10_GG(x1, x2, x3)  =  U10_GG(x1, x2, x3)
U9_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_GGAA(x1, x2, x3, x4, x8)

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

(5) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 5 SCCs with 11 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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
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:

U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)

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:

U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U10_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)
U11_gg(x1, x2, x3)  =  U11_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)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)

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:

U6_GGAA(X, Xs, Y, Ys, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U6_GGAA(X, Xs, Y, Ys, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U8_GGAA(X, Xs, Y, Ys, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U10_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)
U11_gg(x0, x1, x2)
U10_gg(x0, x1, x2)

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

(26) 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:

MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U6_GGAA(X, Xs, Y, Ys, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U8_GGAA(X, Xs, Y, Ys, gt_in_gg(X, Y))

Strictly oriented rules of the TRS R:

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

Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 1 + 2·x1 + x2   
POL(0) = 0   
POL(MERGE_IN_GGAA(x1, x2)) = 2·x1 + 2·x2   
POL(U10_gg(x1, x2, x3)) = 2·x1 + 2·x2 + x3   
POL(U11_gg(x1, x2, x3)) = x1 + x2 + x3   
POL(U6_GGAA(x1, x2, x3, x4, x5)) = 2 + 2·x1 + 2·x2 + 2·x3 + 2·x4 + 2·x5   
POL(U8_GGAA(x1, x2, x3, x4, x5)) = 1 + 2·x1 + 2·x2 + x3 + 2·x4 + x5   
POL(gt_in_gg(x1, x2)) = 2 + 2·x1 + 2·x2   
POL(gt_out_gg(x1, x2)) = 1 + 2·x1 + 2·x2   
POL(le_in_gg(x1, x2)) = x1 + x2   
POL(le_out_gg(x1, x2)) = x1 + x2   
POL(s(x1)) = 2·x1   

(27) Obligation:

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

U6_GGAA(X, Xs, Y, Ys, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys))
U8_GGAA(X, Xs, Y, Ys, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U10_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)
U11_gg(x0, x1, x2)
U10_gg(x0, x1, x2)

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

(28) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes.

(29) TRUE

(30) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)

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

(31) UsableRulesProof (EQUIVALENT transformation)

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

(32) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)

R is empty.
The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)

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

(33) PiDPToQDPProof (SOUND transformation)

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

(34) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs)) → SPLIT_IN_GAAA(Xs)

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

(35) 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_GAAA(.(X, Xs)) → SPLIT_IN_GAAA(Xs)
    The graph contains the following edges 1 > 1

(36) TRUE

(37) Obligation:

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

U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x1, x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x1, x2, x3, x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x1, x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x2, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x1, x2, x3, x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x1, x2, x3, x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x1, x2, x3, x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x1, x2, x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x1, x2, x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg(x1, x2)
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x2, x3, x4, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x1, x2, x3)
gt_out_gg(x1, x2)  =  gt_out_gg(x1, x2)
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x1, x2, x3, x4, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x1, x2, x3, x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x1, x2, x3, x7, x8)

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

(38) PiDPToQDPProof (SOUND transformation)

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

(39) Obligation:

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

U1_GAA(X, Y, Xs, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s)) → U2_GAA(X, Y, Xs, X2s, mergesort_in_gaa(X1s))
U2_GAA(X, Y, Xs, X2s, mergesort_out_gaa(X1s, Y1s)) → MERGESORT_IN_GAA(X2s)
MERGESORT_IN_GAA(.(X, .(Y, Xs))) → U1_GAA(X, Y, Xs, split_in_gaaa(.(X, .(Y, Xs))))
U1_GAA(X, Y, Xs, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s)) → MERGESORT_IN_GAA(X1s)

The TRS R consists of the following rules:

mergesort_in_gaa([]) → mergesort_out_gaa([], [])
mergesort_in_gaa(.(X, [])) → mergesort_out_gaa(.(X, []), .(X, []))
mergesort_in_gaa(.(X, .(Y, Xs))) → U1_gaa(X, Y, Xs, split_in_gaaa(.(X, .(Y, Xs))))
split_in_gaaa([]) → split_out_gaaa([], [], [])
split_in_gaaa(.(X, Xs)) → U5_gaaa(X, Xs, split_in_gaaa(Xs))
U5_gaaa(X, Xs, split_out_gaaa(Xs, Zs, Ys)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs)
U1_gaa(X, Y, Xs, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s)) → U2_gaa(X, Y, Xs, X2s, mergesort_in_gaa(X1s))
U2_gaa(X, Y, Xs, X2s, mergesort_out_gaa(X1s, Y1s)) → U3_gaa(X, Y, Xs, Y1s, mergesort_in_gaa(X2s))
U3_gaa(X, Y, Xs, Y1s, mergesort_out_gaa(X2s, Y2s)) → U4_gaa(X, Y, Xs, merge_in_ggaa(Y1s, Y2s))
merge_in_ggaa([], Xs) → merge_out_ggaa([], Xs, Xs)
merge_in_ggaa(Xs, []) → merge_out_ggaa(Xs, [], Xs)
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U6_ggaa(X, Xs, Y, Ys, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, merge_in_ggaa(Xs, .(Y, Ys)))
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U8_ggaa(X, Xs, Y, Ys, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, merge_in_ggaa(.(X, Xs), Ys))
U9_ggaa(X, Xs, Y, Ys, merge_out_ggaa(.(X, Xs), Ys, Zs)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs))
U7_ggaa(X, Xs, Y, Ys, merge_out_ggaa(Xs, .(Y, Ys), Zs)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs))
U4_gaa(X, Y, Xs, merge_out_ggaa(Y1s, Y2s, Ys)) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys)

The set Q consists of the following terms:

mergesort_in_gaa(x0)
split_in_gaaa(x0)
U5_gaaa(x0, x1, x2)
U1_gaa(x0, x1, x2, x3)
U2_gaa(x0, x1, x2, x3, x4)
U3_gaa(x0, x1, x2, x3, x4)
merge_in_ggaa(x0, x1)
le_in_gg(x0, x1)
U11_gg(x0, x1, x2)
U6_ggaa(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U10_gg(x0, x1, x2)
U8_ggaa(x0, x1, x2, x3, x4)
U9_ggaa(x0, x1, x2, x3, x4)
U7_ggaa(x0, x1, x2, x3, x4)
U4_gaa(x0, x1, x2, x3)

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

(40) 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,f)
split_in: (b,f,f,f)
merge_in: (b,b,f,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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of Prolog

(41) Obligation:

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

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)

(42) 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_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → SPLIT_IN_GAAA(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_GAAA(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_GAA(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → MERGE_IN_GGAA(Y1s, Y2s, Ys, .(H, Ls))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U11_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U10_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x7)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)
U5_GAAA(x1, x2, x3, x4, x5, x6, x7)  =  U5_GAAA(x1, x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x7, x8)
U3_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_GAA(x7, x8)
U4_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U4_GAA(x7)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U11_GG(x1, x2, x3)  =  U11_GG(x3)
U7_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_GGAA(x1, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U10_GG(x1, x2, x3)  =  U10_GG(x3)
U9_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_GGAA(x3, x8)

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

(43) Obligation:

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

MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → SPLIT_IN_GAAA(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_GAAA(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_GAA(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
U3_GAA(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → MERGE_IN_GGAA(Y1s, Y2s, Ys, .(H, Ls))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → LE_IN_GG(X, Y)
LE_IN_GG(s(X), s(Y)) → U11_GG(X, Y, le_in_gg(X, Y))
LE_IN_GG(s(X), s(Y)) → LE_IN_GG(X, Y)
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → GT_IN_GG(X, Y)
GT_IN_GG(s(X), s(Y)) → U10_GG(X, Y, gt_in_gg(X, Y))
GT_IN_GG(s(X), s(Y)) → GT_IN_GG(X, Y)
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_GGAA(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x7)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)
U5_GAAA(x1, x2, x3, x4, x5, x6, x7)  =  U5_GAAA(x1, x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x7, x8)
U3_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_GAA(x7, x8)
U4_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U4_GAA(x7)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)
U11_GG(x1, x2, x3)  =  U11_GG(x3)
U7_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_GGAA(x1, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)
U10_GG(x1, x2, x3)  =  U10_GG(x3)
U9_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_GGAA(x3, x8)

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

(44) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 5 SCCs with 11 less nodes.

(45) Complex Obligation (AND)

(46) 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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
GT_IN_GG(x1, x2)  =  GT_IN_GG(x1, x2)

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

(47) UsableRulesProof (EQUIVALENT transformation)

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

(48) 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

(49) PiDPToQDPProof (EQUIVALENT transformation)

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

(50) 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.

(51) 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

(52) TRUE

(53) 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_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
LE_IN_GG(x1, x2)  =  LE_IN_GG(x1, x2)

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

(54) UsableRulesProof (EQUIVALENT transformation)

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

(55) 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

(56) PiDPToQDPProof (EQUIVALENT transformation)

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

(57) 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.

(58) 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

(59) TRUE

(60) Obligation:

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

U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)

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

(61) UsableRulesProof (EQUIVALENT transformation)

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

(62) Obligation:

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

U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → MERGE_IN_GGAA(Xs, .(Y, Ys), Zs, Ls)
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_GGAA(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → MERGE_IN_GGAA(.(X, Xs), Ys, Zs, Ls)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U10_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)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
MERGE_IN_GGAA(x1, x2, x3, x4)  =  MERGE_IN_GGAA(x1, x2)
U6_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_GGAA(x1, x2, x3, x4, x8)
U8_GGAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_GGAA(x1, x2, x3, x4, x8)

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

(63) PiDPToQDPProof (SOUND transformation)

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

(64) Obligation:

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

U6_GGAA(X, Xs, Y, Ys, le_out_gg) → MERGE_IN_GGAA(Xs, .(Y, Ys))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U6_GGAA(X, Xs, Y, Ys, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U8_GGAA(X, Xs, Y, Ys, gt_in_gg(X, Y))
U8_GGAA(X, Xs, Y, Ys, gt_out_gg) → MERGE_IN_GGAA(.(X, Xs), Ys)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
gt_in_gg(s(X), s(Y)) → U10_gg(gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg
U11_gg(le_out_gg) → le_out_gg
U10_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)
U11_gg(x0)
U10_gg(x0)

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

(65) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U6_GGAA(X, Xs, Y, Ys, le_in_gg(X, Y))
MERGE_IN_GGAA(.(X, Xs), .(Y, Ys)) → U8_GGAA(X, Xs, Y, Ys, gt_in_gg(X, Y))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 1 + x2   
POL(0) = 0   
POL(MERGE_IN_GGAA(x1, x2)) = x1 + x2   
POL(U10_gg(x1)) = 0   
POL(U11_gg(x1)) = 0   
POL(U6_GGAA(x1, x2, x3, x4, x5)) = 1 + x2 + x4   
POL(U8_GGAA(x1, x2, x3, x4, x5)) = 1 + x2 + x4   
POL(gt_in_gg(x1, x2)) = 0   
POL(gt_out_gg) = 0   
POL(le_in_gg(x1, x2)) = 1   
POL(le_out_gg) = 0   
POL(s(x1)) = 0   

The following usable rules [FROCOS05] were oriented: none

(66) Obligation:

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

U6_GGAA(X, Xs, Y, Ys, le_out_gg) → MERGE_IN_GGAA(Xs, .(Y, Ys))
U8_GGAA(X, Xs, Y, Ys, gt_out_gg) → MERGE_IN_GGAA(.(X, Xs), Ys)

The TRS R consists of the following rules:

le_in_gg(s(X), s(Y)) → U11_gg(le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
gt_in_gg(s(X), s(Y)) → U10_gg(gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg
U11_gg(le_out_gg) → le_out_gg
U10_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)
U11_gg(x0)
U10_gg(x0)

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

(67) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes.

(68) TRUE

(69) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)

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

(70) UsableRulesProof (EQUIVALENT transformation)

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

(71) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → SPLIT_IN_GAAA(Xs, Zs, Ys, Ls)

R is empty.
The argument filtering Pi contains the following mapping:
.(x1, x2)  =  .(x1, x2)
SPLIT_IN_GAAA(x1, x2, x3, x4)  =  SPLIT_IN_GAAA(x1)

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

(72) PiDPToQDPProof (SOUND transformation)

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

(73) Obligation:

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

SPLIT_IN_GAAA(.(X, Xs)) → SPLIT_IN_GAAA(Xs)

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

(74) 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_GAAA(.(X, Xs)) → SPLIT_IN_GAAA(Xs)
    The graph contains the following edges 1 > 1

(75) TRUE

(76) Obligation:

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

U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_GAA(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → MERGESORT_IN_GAA(X2s, Y2s, Ls)
MERGESORT_IN_GAA(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_GAA(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
U1_GAA(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → MERGESORT_IN_GAA(X1s, Y1s, Ls)

The TRS R consists of the following rules:

mergesort_in_gaa([], [], Ls) → mergesort_out_gaa([], [], Ls)
mergesort_in_gaa(.(X, []), .(X, []), Ls) → mergesort_out_gaa(.(X, []), .(X, []), Ls)
mergesort_in_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls)) → U1_gaa(X, Y, Xs, Ys, H, Ls, split_in_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls)))
split_in_gaaa([], [], [], Ls) → split_out_gaaa([], [], [], Ls)
split_in_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls)) → U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_in_gaaa(Xs, Zs, Ys, Ls))
U5_gaaa(X, Xs, Ys, Zs, H, Ls, split_out_gaaa(Xs, Zs, Ys, Ls)) → split_out_gaaa(.(X, Xs), .(X, Ys), Zs, .(H, Ls))
U1_gaa(X, Y, Xs, Ys, H, Ls, split_out_gaaa(.(X, .(Y, Xs)), X1s, X2s, .(H, Ls))) → U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_in_gaa(X1s, Y1s, Ls))
U2_gaa(X, Y, Xs, Ys, H, Ls, X2s, mergesort_out_gaa(X1s, Y1s, Ls)) → U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_in_gaa(X2s, Y2s, Ls))
U3_gaa(X, Y, Xs, Ys, H, Ls, Y1s, mergesort_out_gaa(X2s, Y2s, Ls)) → U4_gaa(X, Y, Xs, Ys, H, Ls, merge_in_ggaa(Y1s, Y2s, Ys, .(H, Ls)))
merge_in_ggaa([], Xs, Xs, Ls) → merge_out_ggaa([], Xs, Xs, Ls)
merge_in_ggaa(Xs, [], Xs, Ls) → merge_out_ggaa(Xs, [], Xs, Ls)
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls)) → U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(X, Y, le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg(0, s(0))
le_in_gg(0, 0) → le_out_gg(0, 0)
U11_gg(X, Y, le_out_gg(X, Y)) → le_out_gg(s(X), s(Y))
U6_ggaa(X, Xs, Y, Ys, Zs, H, Ls, le_out_gg(X, Y)) → U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(Xs, .(Y, Ys), Zs, Ls))
merge_in_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls)) → U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(X, Y, gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg(s(0), 0)
U10_gg(X, Y, gt_out_gg(X, Y)) → gt_out_gg(s(X), s(Y))
U8_ggaa(X, Xs, Y, Ys, Zs, H, Ls, gt_out_gg(X, Y)) → U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_in_ggaa(.(X, Xs), Ys, Zs, Ls))
U9_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(.(X, Xs), Ys, Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(Y, Zs), .(H, Ls))
U7_ggaa(X, Xs, Y, Ys, Zs, H, Ls, merge_out_ggaa(Xs, .(Y, Ys), Zs, Ls)) → merge_out_ggaa(.(X, Xs), .(Y, Ys), .(X, Zs), .(H, Ls))
U4_gaa(X, Y, Xs, Ys, H, Ls, merge_out_ggaa(Y1s, Y2s, Ys, .(H, Ls))) → mergesort_out_gaa(.(X, .(Y, Xs)), Ys, .(H, Ls))

The argument filtering Pi contains the following mapping:
mergesort_in_gaa(x1, x2, x3)  =  mergesort_in_gaa(x1)
[]  =  []
mergesort_out_gaa(x1, x2, x3)  =  mergesort_out_gaa(x2)
.(x1, x2)  =  .(x1, x2)
U1_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U1_gaa(x7)
split_in_gaaa(x1, x2, x3, x4)  =  split_in_gaaa(x1)
split_out_gaaa(x1, x2, x3, x4)  =  split_out_gaaa(x2, x3)
U5_gaaa(x1, x2, x3, x4, x5, x6, x7)  =  U5_gaaa(x1, x7)
U2_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_gaa(x7, x8)
U3_gaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U3_gaa(x7, x8)
U4_gaa(x1, x2, x3, x4, x5, x6, x7)  =  U4_gaa(x7)
merge_in_ggaa(x1, x2, x3, x4)  =  merge_in_ggaa(x1, x2)
merge_out_ggaa(x1, x2, x3, x4)  =  merge_out_ggaa(x3)
U6_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U6_ggaa(x1, x2, x3, x4, x8)
le_in_gg(x1, x2)  =  le_in_gg(x1, x2)
s(x1)  =  s(x1)
U11_gg(x1, x2, x3)  =  U11_gg(x3)
0  =  0
le_out_gg(x1, x2)  =  le_out_gg
U7_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U7_ggaa(x1, x8)
U8_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U8_ggaa(x1, x2, x3, x4, x8)
gt_in_gg(x1, x2)  =  gt_in_gg(x1, x2)
U10_gg(x1, x2, x3)  =  U10_gg(x3)
gt_out_gg(x1, x2)  =  gt_out_gg
U9_ggaa(x1, x2, x3, x4, x5, x6, x7, x8)  =  U9_ggaa(x3, x8)
MERGESORT_IN_GAA(x1, x2, x3)  =  MERGESORT_IN_GAA(x1)
U1_GAA(x1, x2, x3, x4, x5, x6, x7)  =  U1_GAA(x7)
U2_GAA(x1, x2, x3, x4, x5, x6, x7, x8)  =  U2_GAA(x7, x8)

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

(77) PiDPToQDPProof (SOUND transformation)

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

(78) Obligation:

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

U1_GAA(split_out_gaaa(X1s, X2s)) → U2_GAA(X2s, mergesort_in_gaa(X1s))
U2_GAA(X2s, mergesort_out_gaa(Y1s)) → MERGESORT_IN_GAA(X2s)
MERGESORT_IN_GAA(.(X, .(Y, Xs))) → U1_GAA(split_in_gaaa(.(X, .(Y, Xs))))
U1_GAA(split_out_gaaa(X1s, X2s)) → MERGESORT_IN_GAA(X1s)

The TRS R consists of the following rules:

mergesort_in_gaa([]) → mergesort_out_gaa([])
mergesort_in_gaa(.(X, [])) → mergesort_out_gaa(.(X, []))
mergesort_in_gaa(.(X, .(Y, Xs))) → U1_gaa(split_in_gaaa(.(X, .(Y, Xs))))
split_in_gaaa([]) → split_out_gaaa([], [])
split_in_gaaa(.(X, Xs)) → U5_gaaa(X, split_in_gaaa(Xs))
U5_gaaa(X, split_out_gaaa(Zs, Ys)) → split_out_gaaa(.(X, Ys), Zs)
U1_gaa(split_out_gaaa(X1s, X2s)) → U2_gaa(X2s, mergesort_in_gaa(X1s))
U2_gaa(X2s, mergesort_out_gaa(Y1s)) → U3_gaa(Y1s, mergesort_in_gaa(X2s))
U3_gaa(Y1s, mergesort_out_gaa(Y2s)) → U4_gaa(merge_in_ggaa(Y1s, Y2s))
merge_in_ggaa([], Xs) → merge_out_ggaa(Xs)
merge_in_ggaa(Xs, []) → merge_out_ggaa(Xs)
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U6_ggaa(X, Xs, Y, Ys, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U11_gg(le_out_gg) → le_out_gg
U6_ggaa(X, Xs, Y, Ys, le_out_gg) → U7_ggaa(X, merge_in_ggaa(Xs, .(Y, Ys)))
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U8_ggaa(X, Xs, Y, Ys, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg
U10_gg(gt_out_gg) → gt_out_gg
U8_ggaa(X, Xs, Y, Ys, gt_out_gg) → U9_ggaa(Y, merge_in_ggaa(.(X, Xs), Ys))
U9_ggaa(Y, merge_out_ggaa(Zs)) → merge_out_ggaa(.(Y, Zs))
U7_ggaa(X, merge_out_ggaa(Zs)) → merge_out_ggaa(.(X, Zs))
U4_gaa(merge_out_ggaa(Ys)) → mergesort_out_gaa(Ys)

The set Q consists of the following terms:

mergesort_in_gaa(x0)
split_in_gaaa(x0)
U5_gaaa(x0, x1)
U1_gaa(x0)
U2_gaa(x0, x1)
U3_gaa(x0, x1)
merge_in_ggaa(x0, x1)
le_in_gg(x0, x1)
U11_gg(x0)
U6_ggaa(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U10_gg(x0)
U8_ggaa(x0, x1, x2, x3, x4)
U9_ggaa(x0, x1)
U7_ggaa(x0, x1)
U4_gaa(x0)

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

(79) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


MERGESORT_IN_GAA(.(X, .(Y, Xs))) → U1_GAA(split_in_gaaa(.(X, .(Y, Xs))))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO]:

POL(U1_GAA(x1)) = 1 +
[0,1]
·x1

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

POL(U2_GAA(x1, x2)) = 1 +
[1,1]
·x1 +
[0,0]
·x2

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

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

POL(MERGESORT_IN_GAA(x1)) = 1 +
[1,1]
·x1

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

POL(split_in_gaaa(x1)) =
/0\
\0/
+
/10\
\01/
·x1

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

POL(U1_gaa(x1)) =
/1\
\0/
+
/00\
\00/
·x1

POL(U5_gaaa(x1, x2)) =
/0\
\1/
+
/00\
\00/
·x1 +
/01\
\11/
·x2

POL(U2_gaa(x1, x2)) =
/0\
\0/
+
/10\
\10/
·x1 +
/11\
\00/
·x2

POL(U3_gaa(x1, x2)) =
/1\
\1/
+
/10\
\11/
·x1 +
/11\
\01/
·x2

POL(U4_gaa(x1)) =
/0\
\0/
+
/11\
\00/
·x1

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

POL(merge_out_ggaa(x1)) =
/0\
\0/
+
/11\
\11/
·x1

POL(U6_ggaa(x1, x2, x3, x4, x5)) =
/1\
\0/
+
/00\
\11/
·x1 +
/11\
\11/
·x2 +
/00\
\00/
·x3 +
/01\
\11/
·x4 +
/00\
\00/
·x5

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

POL(U8_ggaa(x1, x2, x3, x4, x5)) =
/1\
\0/
+
/10\
\11/
·x1 +
/10\
\10/
·x2 +
/01\
\01/
·x3 +
/00\
\11/
·x4 +
/01\
\00/
·x5

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

POL(s(x1)) =
/0\
\0/
+
/01\
\11/
·x1

POL(U11_gg(x1)) =
/1\
\1/
+
/00\
\11/
·x1

POL(0) =
/0\
\0/

POL(le_out_gg) =
/0\
\0/

POL(U7_ggaa(x1, x2)) =
/1\
\0/
+
/11\
\01/
·x1 +
/00\
\00/
·x2

POL(U10_gg(x1)) =
/0\
\0/
+
/01\
\01/
·x1

POL(gt_out_gg) =
/1\
\0/

POL(U9_ggaa(x1, x2)) =
/0\
\0/
+
/11\
\10/
·x1 +
/00\
\00/
·x2

The following usable rules [FROCOS05] were oriented:

split_in_gaaa(.(X, Xs)) → U5_gaaa(X, split_in_gaaa(Xs))
split_in_gaaa([]) → split_out_gaaa([], [])
U5_gaaa(X, split_out_gaaa(Zs, Ys)) → split_out_gaaa(.(X, Ys), Zs)

(80) Obligation:

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

U1_GAA(split_out_gaaa(X1s, X2s)) → U2_GAA(X2s, mergesort_in_gaa(X1s))
U2_GAA(X2s, mergesort_out_gaa(Y1s)) → MERGESORT_IN_GAA(X2s)
U1_GAA(split_out_gaaa(X1s, X2s)) → MERGESORT_IN_GAA(X1s)

The TRS R consists of the following rules:

mergesort_in_gaa([]) → mergesort_out_gaa([])
mergesort_in_gaa(.(X, [])) → mergesort_out_gaa(.(X, []))
mergesort_in_gaa(.(X, .(Y, Xs))) → U1_gaa(split_in_gaaa(.(X, .(Y, Xs))))
split_in_gaaa([]) → split_out_gaaa([], [])
split_in_gaaa(.(X, Xs)) → U5_gaaa(X, split_in_gaaa(Xs))
U5_gaaa(X, split_out_gaaa(Zs, Ys)) → split_out_gaaa(.(X, Ys), Zs)
U1_gaa(split_out_gaaa(X1s, X2s)) → U2_gaa(X2s, mergesort_in_gaa(X1s))
U2_gaa(X2s, mergesort_out_gaa(Y1s)) → U3_gaa(Y1s, mergesort_in_gaa(X2s))
U3_gaa(Y1s, mergesort_out_gaa(Y2s)) → U4_gaa(merge_in_ggaa(Y1s, Y2s))
merge_in_ggaa([], Xs) → merge_out_ggaa(Xs)
merge_in_ggaa(Xs, []) → merge_out_ggaa(Xs)
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U6_ggaa(X, Xs, Y, Ys, le_in_gg(X, Y))
le_in_gg(s(X), s(Y)) → U11_gg(le_in_gg(X, Y))
le_in_gg(0, s(0)) → le_out_gg
le_in_gg(0, 0) → le_out_gg
U11_gg(le_out_gg) → le_out_gg
U6_ggaa(X, Xs, Y, Ys, le_out_gg) → U7_ggaa(X, merge_in_ggaa(Xs, .(Y, Ys)))
merge_in_ggaa(.(X, Xs), .(Y, Ys)) → U8_ggaa(X, Xs, Y, Ys, gt_in_gg(X, Y))
gt_in_gg(s(X), s(Y)) → U10_gg(gt_in_gg(X, Y))
gt_in_gg(s(0), 0) → gt_out_gg
U10_gg(gt_out_gg) → gt_out_gg
U8_ggaa(X, Xs, Y, Ys, gt_out_gg) → U9_ggaa(Y, merge_in_ggaa(.(X, Xs), Ys))
U9_ggaa(Y, merge_out_ggaa(Zs)) → merge_out_ggaa(.(Y, Zs))
U7_ggaa(X, merge_out_ggaa(Zs)) → merge_out_ggaa(.(X, Zs))
U4_gaa(merge_out_ggaa(Ys)) → mergesort_out_gaa(Ys)

The set Q consists of the following terms:

mergesort_in_gaa(x0)
split_in_gaaa(x0)
U5_gaaa(x0, x1)
U1_gaa(x0)
U2_gaa(x0, x1)
U3_gaa(x0, x1)
merge_in_ggaa(x0, x1)
le_in_gg(x0, x1)
U11_gg(x0)
U6_ggaa(x0, x1, x2, x3, x4)
gt_in_gg(x0, x1)
U10_gg(x0)
U8_ggaa(x0, x1, x2, x3, x4)
U9_ggaa(x0, x1)
U7_ggaa(x0, x1)
U4_gaa(x0)

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

(81) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 3 less nodes.

(82) TRUE