(0) Obligation:

Clauses:

fold(X, [], Z) :- ','(!, eq(X, Z)).
fold(X, Y, Z) :- ','(head(Y, H), ','(tail(Y, T), ','(myop(X, H, V), fold(V, T, Z)))).
myop(a, b, a).
head([], X1).
head(.(H, X2), H).
tail([], []).
tail(.(X3, T), T).
eq(X, X).

Queries:

fold(g,g,a).

(1) CutEliminatorProof (SOUND transformation)

Eliminated all cuts by simply ignoring them[PROLOG].

(2) Obligation:

Clauses:

fold(X, [], Z) :- eq(X, Z).
fold(X, Y, Z) :- ','(head(Y, H), ','(tail(Y, T), ','(myop(X, H, V), fold(V, T, Z)))).
myop(a, b, a).
head([], X1).
head(.(H, X2), H).
tail([], []).
tail(.(X3, T), T).
eq(X, X).

Queries:

fold(g,g,a).

(3) PrologToPiTRSProof (SOUND transformation)

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

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x1, x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x1, x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x1, x2, x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x2, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x1, x2, x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x1, x2, x4)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of Prolog

(4) Obligation:

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

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x1, x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x1, x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x1, x2, x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x2, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x1, x2, x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x1, x2, x4)

(5) 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:

FOLD_IN_GGA(X, [], Z) → U1_GGA(X, Z, eq_in_ga(X, Z))
FOLD_IN_GGA(X, [], Z) → EQ_IN_GA(X, Z)
FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
FOLD_IN_GGA(X, Y, Z) → HEAD_IN_GA(Y, H)
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → TAIL_IN_GA(Y, T)
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → MYOP_IN_GAA(X, H, V)
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_GGA(X, Y, Z, fold_in_gga(V, T, Z))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x1, x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x1, x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x1, x2, x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x2, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x1, x2, x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x1, x2, x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U1_GGA(x1, x2, x3)  =  U1_GGA(x1, x3)
EQ_IN_GA(x1, x2)  =  EQ_IN_GA(x1)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
HEAD_IN_GA(x1, x2)  =  HEAD_IN_GA(x1)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x2, x5)
TAIL_IN_GA(x1, x2)  =  TAIL_IN_GA(x1)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x1, x2, x5, x6)
MYOP_IN_GAA(x1, x2, x3)  =  MYOP_IN_GAA(x1)
U5_GGA(x1, x2, x3, x4)  =  U5_GGA(x1, x2, x4)

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

(6) Obligation:

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

FOLD_IN_GGA(X, [], Z) → U1_GGA(X, Z, eq_in_ga(X, Z))
FOLD_IN_GGA(X, [], Z) → EQ_IN_GA(X, Z)
FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
FOLD_IN_GGA(X, Y, Z) → HEAD_IN_GA(Y, H)
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → TAIL_IN_GA(Y, T)
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → MYOP_IN_GAA(X, H, V)
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_GGA(X, Y, Z, fold_in_gga(V, T, Z))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x1, x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x1, x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x1, x2, x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x2, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x1, x2, x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x1, x2, x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U1_GGA(x1, x2, x3)  =  U1_GGA(x1, x3)
EQ_IN_GA(x1, x2)  =  EQ_IN_GA(x1)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
HEAD_IN_GA(x1, x2)  =  HEAD_IN_GA(x1)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x2, x5)
TAIL_IN_GA(x1, x2)  =  TAIL_IN_GA(x1)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x1, x2, x5, x6)
MYOP_IN_GAA(x1, x2, x3)  =  MYOP_IN_GAA(x1)
U5_GGA(x1, x2, x3, x4)  =  U5_GGA(x1, x2, x4)

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

(7) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 1 SCC with 6 less nodes.

(8) Obligation:

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

FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x1, x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x1, x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x1, x2, x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x2, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x1, x2, x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x1, x2, x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x2, x5)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x1, x2, x5, x6)

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

(9) UsableRulesProof (EQUIVALENT transformation)

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

(10) Obligation:

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

FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)

The argument filtering Pi contains the following mapping:
[]  =  []
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga(x1)
.(x1, x2)  =  .(x1, x2)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x1, x2)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x1, x2, x3)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x2, x5)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x1, x2, x5, x6)

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

(11) PiDPToQDPProof (SOUND transformation)

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

(12) Obligation:

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

FOLD_IN_GGA(X, Y) → U2_GGA(X, Y, head_in_ga(Y))
U2_GGA(X, Y, head_out_ga(Y)) → U3_GGA(X, Y, tail_in_ga(Y))
U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)

The TRS R consists of the following rules:

head_in_ga([]) → head_out_ga([])
head_in_ga(.(H, X2)) → head_out_ga(.(H, X2))
tail_in_ga([]) → tail_out_ga([], [])
tail_in_ga(.(X3, T)) → tail_out_ga(.(X3, T), T)
myop_in_gaa(a) → myop_out_gaa(a, b, a)

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(13) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule FOLD_IN_GGA(X, Y) → U2_GGA(X, Y, head_in_ga(Y)) at position [2] we obtained the following new rules [LPAR04]:

FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))

(14) Obligation:

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

U2_GGA(X, Y, head_out_ga(Y)) → U3_GGA(X, Y, tail_in_ga(Y))
U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))

The TRS R consists of the following rules:

head_in_ga([]) → head_out_ga([])
head_in_ga(.(H, X2)) → head_out_ga(.(H, X2))
tail_in_ga([]) → tail_out_ga([], [])
tail_in_ga(.(X3, T)) → tail_out_ga(.(X3, T), T)
myop_in_gaa(a) → myop_out_gaa(a, b, a)

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(15) UsableRulesProof (EQUIVALENT transformation)

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

(16) Obligation:

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

U2_GGA(X, Y, head_out_ga(Y)) → U3_GGA(X, Y, tail_in_ga(Y))
U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)
tail_in_ga([]) → tail_out_ga([], [])
tail_in_ga(.(X3, T)) → tail_out_ga(.(X3, T), T)

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(17) QReductionProof (EQUIVALENT transformation)

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

head_in_ga(x0)

(18) Obligation:

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

U2_GGA(X, Y, head_out_ga(Y)) → U3_GGA(X, Y, tail_in_ga(Y))
U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)
tail_in_ga([]) → tail_out_ga([], [])
tail_in_ga(.(X3, T)) → tail_out_ga(.(X3, T), T)

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(19) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule U2_GGA(X, Y, head_out_ga(Y)) → U3_GGA(X, Y, tail_in_ga(Y)) at position [2] we obtained the following new rules [LPAR04]:

U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))

(20) Obligation:

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

U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)
tail_in_ga([]) → tail_out_ga([], [])
tail_in_ga(.(X3, T)) → tail_out_ga(.(X3, T), T)

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(21) UsableRulesProof (EQUIVALENT transformation)

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

(22) Obligation:

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

U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(23) QReductionProof (EQUIVALENT transformation)

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

tail_in_ga(x0)

(24) Obligation:

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

U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X))
U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)

The set Q consists of the following terms:

myop_in_gaa(x0)

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

(25) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule U3_GGA(X, Y, tail_out_ga(Y, T)) → U4_GGA(X, Y, T, myop_in_gaa(X)) at position [3] we obtained the following new rules [LPAR04]:

U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))

(26) Obligation:

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

U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(a, b, a)

The set Q consists of the following terms:

myop_in_gaa(x0)

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

(27) UsableRulesProof (EQUIVALENT transformation)

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

(28) Obligation:

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

U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))

R is empty.
The set Q consists of the following terms:

myop_in_gaa(x0)

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

(29) QReductionProof (EQUIVALENT transformation)

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

myop_in_gaa(x0)

(30) Obligation:

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

U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))

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

(31) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U4_GGA(X, Y, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T) we obtained the following new rules [LPAR04]:

U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)

(32) Obligation:

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

FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([]))
FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)

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

(33) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga([])) we obtained the following new rules [LPAR04]:

FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))

(34) Obligation:

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

FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1)))
U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))

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

(35) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule FOLD_IN_GGA(y0, .(x0, x1)) → U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) we obtained the following new rules [LPAR04]:

FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))

(36) Obligation:

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

U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], []))
U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))

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

(37) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U2_GGA(y0, [], head_out_ga([])) → U3_GGA(y0, [], tail_out_ga([], [])) we obtained the following new rules [LPAR04]:

U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))

(38) Obligation:

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

U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))

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

(39) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U2_GGA(y0, .(x0, x1), head_out_ga(.(x0, x1))) → U3_GGA(y0, .(x0, x1), tail_out_ga(.(x0, x1), x1)) we obtained the following new rules [LPAR04]:

U2_GGA(a, .(z0, z1), head_out_ga(.(z0, z1))) → U3_GGA(a, .(z0, z1), tail_out_ga(.(z0, z1), z1))

(40) Obligation:

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

U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U2_GGA(a, .(z0, z1), head_out_ga(.(z0, z1))) → U3_GGA(a, .(z0, z1), tail_out_ga(.(z0, z1), z1))

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

(41) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO]:

POL(U3_GGA(x1, x2, x3)) = 0 +
[0,0]
·x1 +
[0,0]
·x2 +
[1,0]
·x3

POL(a) =
/0\
\0/

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

POL(U4_GGA(x1, x2, x3, x4)) = 0 +
[0,0]
·x1 +
[0,0]
·x2 +
[1,0]
·x3 +
[0,0]
·x4

POL(myop_out_gaa(x1, x2, x3)) =
/0\
\0/
+
/00\
\00/
·x1 +
/00\
\00/
·x2 +
/00\
\00/
·x3

POL(b) =
/0\
\0/

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

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

POL(U2_GGA(x1, x2, x3)) = 0 +
[0,0]
·x1 +
[0,1]
·x2 +
[0,0]
·x3

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

POL(.(x1, x2)) =
/1\
\0/
+
/11\
\10/
·x1 +
/10\
\10/
·x2

The following usable rules [FROCOS05] were oriented: none

(42) Obligation:

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

U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U2_GGA(a, .(z0, z1), head_out_ga(.(z0, z1))) → U3_GGA(a, .(z0, z1), tail_out_ga(.(z0, z1), z1))

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

(43) DependencyGraphProof (EQUIVALENT transformation)

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

(44) Obligation:

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

U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))

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

(45) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a)) we obtained the following new rules [LPAR04]:

U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a))

(46) Obligation:

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

U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a))

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

(47) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a)) we obtained the following new rules [LPAR04]:

U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a))

(48) Obligation:

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

U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a))

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

(49) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1) we obtained the following new rules [LPAR04]:

U4_GGA(a, [], [], myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, [])

(50) Obligation:

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

FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))
U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a))
U4_GGA(a, [], [], myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, [])

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

(51) NonTerminationProof (EQUIVALENT transformation)

We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by narrowing to the left:

s = U2_GGA(a, [], head_out_ga([])) evaluates to t =U2_GGA(a, [], head_out_ga([]))

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
  • Semiunifier: [ ]
  • Matcher: [ ]




Rewriting sequence

U2_GGA(a, [], head_out_ga([]))U3_GGA(a, [], tail_out_ga([], []))
with rule U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], [])) at position [] and matcher [ ]

U3_GGA(a, [], tail_out_ga([], []))U4_GGA(a, [], [], myop_out_gaa(a, b, a))
with rule U3_GGA(a, [], tail_out_ga([], [])) → U4_GGA(a, [], [], myop_out_gaa(a, b, a)) at position [] and matcher [ ]

U4_GGA(a, [], [], myop_out_gaa(a, b, a))FOLD_IN_GGA(a, [])
with rule U4_GGA(a, [], [], myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, []) at position [] and matcher [ ]

FOLD_IN_GGA(a, [])U2_GGA(a, [], head_out_ga([]))
with rule FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))

Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence


All these steps are and every following step will be a correct step w.r.t to Q.



(52) FALSE

(53) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


U2_GGA(a, .(z0, z1), head_out_ga(.(z0, z1))) → U3_GGA(a, .(z0, z1), tail_out_ga(.(z0, z1), z1))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:

POL(.(x1, x2)) = 1 + x2   
POL(FOLD_IN_GGA(x1, x2)) = x2   
POL(U2_GGA(x1, x2, x3)) = x2   
POL(U3_GGA(x1, x2, x3)) = x3   
POL(U4_GGA(x1, x2, x3, x4)) = x3   
POL([]) = 0   
POL(a) = 0   
POL(b) = 0   
POL(head_out_ga(x1)) = 0   
POL(myop_out_gaa(x1, x2, x3)) = 0   
POL(tail_out_ga(x1, x2)) = x2   

The following usable rules [FROCOS05] were oriented: none

(54) Obligation:

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

U3_GGA(a, y1, tail_out_ga(y1, y2)) → U4_GGA(a, y1, y2, myop_out_gaa(a, b, a))
U4_GGA(a, z0, z1, myop_out_gaa(a, b, a)) → FOLD_IN_GGA(a, z1)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga([]))
FOLD_IN_GGA(a, .(x1, x2)) → U2_GGA(a, .(x1, x2), head_out_ga(.(x1, x2)))
U2_GGA(a, [], head_out_ga([])) → U3_GGA(a, [], tail_out_ga([], []))

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

(55) PrologToPiTRSProof (SOUND transformation)

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

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x4)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of Prolog

(56) Obligation:

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

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x4)

(57) 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:

FOLD_IN_GGA(X, [], Z) → U1_GGA(X, Z, eq_in_ga(X, Z))
FOLD_IN_GGA(X, [], Z) → EQ_IN_GA(X, Z)
FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
FOLD_IN_GGA(X, Y, Z) → HEAD_IN_GA(Y, H)
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → TAIL_IN_GA(Y, T)
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → MYOP_IN_GAA(X, H, V)
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_GGA(X, Y, Z, fold_in_gga(V, T, Z))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U1_GGA(x1, x2, x3)  =  U1_GGA(x3)
EQ_IN_GA(x1, x2)  =  EQ_IN_GA(x1)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
HEAD_IN_GA(x1, x2)  =  HEAD_IN_GA(x1)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x5)
TAIL_IN_GA(x1, x2)  =  TAIL_IN_GA(x1)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x5, x6)
MYOP_IN_GAA(x1, x2, x3)  =  MYOP_IN_GAA(x1)
U5_GGA(x1, x2, x3, x4)  =  U5_GGA(x4)

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

(58) Obligation:

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

FOLD_IN_GGA(X, [], Z) → U1_GGA(X, Z, eq_in_ga(X, Z))
FOLD_IN_GGA(X, [], Z) → EQ_IN_GA(X, Z)
FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
FOLD_IN_GGA(X, Y, Z) → HEAD_IN_GA(Y, H)
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → TAIL_IN_GA(Y, T)
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → MYOP_IN_GAA(X, H, V)
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_GGA(X, Y, Z, fold_in_gga(V, T, Z))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U1_GGA(x1, x2, x3)  =  U1_GGA(x3)
EQ_IN_GA(x1, x2)  =  EQ_IN_GA(x1)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
HEAD_IN_GA(x1, x2)  =  HEAD_IN_GA(x1)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x5)
TAIL_IN_GA(x1, x2)  =  TAIL_IN_GA(x1)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x5, x6)
MYOP_IN_GAA(x1, x2, x3)  =  MYOP_IN_GAA(x1)
U5_GGA(x1, x2, x3, x4)  =  U5_GGA(x4)

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

(59) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 1 SCC with 6 less nodes.

(60) Obligation:

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

FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

fold_in_gga(X, [], Z) → U1_gga(X, Z, eq_in_ga(X, Z))
eq_in_ga(X, X) → eq_out_ga(X, X)
U1_gga(X, Z, eq_out_ga(X, Z)) → fold_out_gga(X, [], Z)
fold_in_gga(X, Y, Z) → U2_gga(X, Y, Z, head_in_ga(Y, H))
head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
U2_gga(X, Y, Z, head_out_ga(Y, H)) → U3_gga(X, Y, Z, H, tail_in_ga(Y, T))
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
U3_gga(X, Y, Z, H, tail_out_ga(Y, T)) → U4_gga(X, Y, Z, H, T, myop_in_gaa(X, H, V))
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)
U4_gga(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → U5_gga(X, Y, Z, fold_in_gga(V, T, Z))
U5_gga(X, Y, Z, fold_out_gga(V, T, Z)) → fold_out_gga(X, Y, Z)

The argument filtering Pi contains the following mapping:
fold_in_gga(x1, x2, x3)  =  fold_in_gga(x1, x2)
[]  =  []
U1_gga(x1, x2, x3)  =  U1_gga(x3)
eq_in_ga(x1, x2)  =  eq_in_ga(x1)
eq_out_ga(x1, x2)  =  eq_out_ga(x2)
fold_out_gga(x1, x2, x3)  =  fold_out_gga(x3)
U2_gga(x1, x2, x3, x4)  =  U2_gga(x1, x2, x4)
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
U3_gga(x1, x2, x3, x4, x5)  =  U3_gga(x1, x5)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
U4_gga(x1, x2, x3, x4, x5, x6)  =  U4_gga(x5, x6)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
U5_gga(x1, x2, x3, x4)  =  U5_gga(x4)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x5)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x5, x6)

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:

FOLD_IN_GGA(X, Y, Z) → U2_GGA(X, Y, Z, head_in_ga(Y, H))
U2_GGA(X, Y, Z, head_out_ga(Y, H)) → U3_GGA(X, Y, Z, H, tail_in_ga(Y, T))
U3_GGA(X, Y, Z, H, tail_out_ga(Y, T)) → U4_GGA(X, Y, Z, H, T, myop_in_gaa(X, H, V))
U4_GGA(X, Y, Z, H, T, myop_out_gaa(X, H, V)) → FOLD_IN_GGA(V, T, Z)

The TRS R consists of the following rules:

head_in_ga([], X1) → head_out_ga([], X1)
head_in_ga(.(H, X2), H) → head_out_ga(.(H, X2), H)
tail_in_ga([], []) → tail_out_ga([], [])
tail_in_ga(.(X3, T), T) → tail_out_ga(.(X3, T), T)
myop_in_gaa(a, b, a) → myop_out_gaa(a, b, a)

The argument filtering Pi contains the following mapping:
[]  =  []
head_in_ga(x1, x2)  =  head_in_ga(x1)
head_out_ga(x1, x2)  =  head_out_ga
.(x1, x2)  =  .(x1, x2)
tail_in_ga(x1, x2)  =  tail_in_ga(x1)
tail_out_ga(x1, x2)  =  tail_out_ga(x2)
myop_in_gaa(x1, x2, x3)  =  myop_in_gaa(x1)
a  =  a
myop_out_gaa(x1, x2, x3)  =  myop_out_gaa(x2, x3)
FOLD_IN_GGA(x1, x2, x3)  =  FOLD_IN_GGA(x1, x2)
U2_GGA(x1, x2, x3, x4)  =  U2_GGA(x1, x2, x4)
U3_GGA(x1, x2, x3, x4, x5)  =  U3_GGA(x1, x5)
U4_GGA(x1, x2, x3, x4, x5, x6)  =  U4_GGA(x5, x6)

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:

FOLD_IN_GGA(X, Y) → U2_GGA(X, Y, head_in_ga(Y))
U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y))
U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)

The TRS R consists of the following rules:

head_in_ga([]) → head_out_ga
head_in_ga(.(H, X2)) → head_out_ga
tail_in_ga([]) → tail_out_ga([])
tail_in_ga(.(X3, T)) → tail_out_ga(T)
myop_in_gaa(a) → myop_out_gaa(b, a)

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(65) UsableRulesReductionPairsProof (EQUIVALENT transformation)

By using the usable rules with reduction pair processor [LPAR04] with a polynomial ordering [POLO], all dependency pairs and the corresponding usable rules [FROCOS05] can be oriented non-strictly. All non-usable rules are removed, and those dependency pairs and usable rules that have been oriented strictly or contain non-usable symbols in their left-hand side are removed as well.

No dependency pairs are removed.

The following rules are removed from R:

tail_in_ga(.(X3, T)) → tail_out_ga(T)
head_in_ga(.(H, X2)) → head_out_ga
Used ordering: POLO with Polynomial interpretation [POLO]:

POL(.(x1, x2)) = x1 + 2·x2   
POL(FOLD_IN_GGA(x1, x2)) = 2·x1 + 2·x2   
POL(U2_GGA(x1, x2, x3)) = 2·x1 + x2 + x3   
POL(U3_GGA(x1, x2)) = 2·x1 + x2   
POL(U4_GGA(x1, x2)) = 2·x1 + x2   
POL([]) = 0   
POL(a) = 0   
POL(b) = 0   
POL(head_in_ga(x1)) = x1   
POL(head_out_ga) = 0   
POL(myop_in_gaa(x1)) = 2·x1   
POL(myop_out_gaa(x1, x2)) = 2·x1 + 2·x2   
POL(tail_in_ga(x1)) = x1   
POL(tail_out_ga(x1)) = 2·x1   

(66) Obligation:

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

FOLD_IN_GGA(X, Y) → U2_GGA(X, Y, head_in_ga(Y))
U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y))
U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)
tail_in_ga([]) → tail_out_ga([])
head_in_ga([]) → head_out_ga

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(67) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule FOLD_IN_GGA(X, Y) → U2_GGA(X, Y, head_in_ga(Y)) at position [2] we obtained the following new rules [LPAR04]:

FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)

(68) Obligation:

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

U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y))
U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)
tail_in_ga([]) → tail_out_ga([])
head_in_ga([]) → head_out_ga

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(69) UsableRulesProof (EQUIVALENT transformation)

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

(70) Obligation:

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

U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y))
U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)
tail_in_ga([]) → tail_out_ga([])

The set Q consists of the following terms:

head_in_ga(x0)
tail_in_ga(x0)
myop_in_gaa(x0)

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

(71) QReductionProof (EQUIVALENT transformation)

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

head_in_ga(x0)

(72) Obligation:

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

U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y))
U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)
tail_in_ga([]) → tail_out_ga([])

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(73) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule U2_GGA(X, Y, head_out_ga) → U3_GGA(X, tail_in_ga(Y)) at position [1] we obtained the following new rules [LPAR04]:

U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))

(74) Obligation:

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

U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)
tail_in_ga([]) → tail_out_ga([])

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(75) UsableRulesProof (EQUIVALENT transformation)

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

(76) Obligation:

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

U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)

The set Q consists of the following terms:

tail_in_ga(x0)
myop_in_gaa(x0)

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

(77) QReductionProof (EQUIVALENT transformation)

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

tail_in_ga(x0)

(78) Obligation:

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

U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X))
U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)

The set Q consists of the following terms:

myop_in_gaa(x0)

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

(79) Narrowing (SOUND transformation)

By narrowing [LPAR04] the rule U3_GGA(X, tail_out_ga(T)) → U4_GGA(T, myop_in_gaa(X)) at position [1] we obtained the following new rules [LPAR04]:

U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))

(80) Obligation:

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

U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))
U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))

The TRS R consists of the following rules:

myop_in_gaa(a) → myop_out_gaa(b, a)

The set Q consists of the following terms:

myop_in_gaa(x0)

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

(81) UsableRulesProof (EQUIVALENT transformation)

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

(82) Obligation:

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

U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))
U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))

R is empty.
The set Q consists of the following terms:

myop_in_gaa(x0)

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

(83) QReductionProof (EQUIVALENT transformation)

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

myop_in_gaa(x0)

(84) Obligation:

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

U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T)
FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))
U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))

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

(85) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U4_GGA(T, myop_out_gaa(H, V)) → FOLD_IN_GGA(V, T) we obtained the following new rules [LPAR04]:

U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0)

(86) Obligation:

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

FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga)
U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))
U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))
U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0)

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

(87) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule FOLD_IN_GGA(y0, []) → U2_GGA(y0, [], head_out_ga) we obtained the following new rules [LPAR04]:

FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)

(88) Obligation:

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

U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([]))
U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))
U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)

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

(89) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U2_GGA(y0, [], head_out_ga) → U3_GGA(y0, tail_out_ga([])) we obtained the following new rules [LPAR04]:

U2_GGA(a, [], head_out_ga) → U3_GGA(a, tail_out_ga([]))

(90) Obligation:

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

U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a))
U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)
U2_GGA(a, [], head_out_ga) → U3_GGA(a, tail_out_ga([]))

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

(91) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U3_GGA(a, tail_out_ga(y1)) → U4_GGA(y1, myop_out_gaa(b, a)) we obtained the following new rules [LPAR04]:

U3_GGA(a, tail_out_ga([])) → U4_GGA([], myop_out_gaa(b, a))

(92) Obligation:

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

U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0)
FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)
U2_GGA(a, [], head_out_ga) → U3_GGA(a, tail_out_ga([]))
U3_GGA(a, tail_out_ga([])) → U4_GGA([], myop_out_gaa(b, a))

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

(93) Instantiation (EQUIVALENT transformation)

By instantiating [LPAR04] the rule U4_GGA(z0, myop_out_gaa(b, a)) → FOLD_IN_GGA(a, z0) we obtained the following new rules [LPAR04]:

U4_GGA([], myop_out_gaa(b, a)) → FOLD_IN_GGA(a, [])

(94) Obligation:

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

FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)
U2_GGA(a, [], head_out_ga) → U3_GGA(a, tail_out_ga([]))
U3_GGA(a, tail_out_ga([])) → U4_GGA([], myop_out_gaa(b, a))
U4_GGA([], myop_out_gaa(b, a)) → FOLD_IN_GGA(a, [])

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

(95) NonTerminationProof (EQUIVALENT transformation)

We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by narrowing to the left:

s = U2_GGA(a, [], head_out_ga) evaluates to t =U2_GGA(a, [], head_out_ga)

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
  • Matcher: [ ]
  • Semiunifier: [ ]




Rewriting sequence

U2_GGA(a, [], head_out_ga)U3_GGA(a, tail_out_ga([]))
with rule U2_GGA(a, [], head_out_ga) → U3_GGA(a, tail_out_ga([])) at position [] and matcher [ ]

U3_GGA(a, tail_out_ga([]))U4_GGA([], myop_out_gaa(b, a))
with rule U3_GGA(a, tail_out_ga([])) → U4_GGA([], myop_out_gaa(b, a)) at position [] and matcher [ ]

U4_GGA([], myop_out_gaa(b, a))FOLD_IN_GGA(a, [])
with rule U4_GGA([], myop_out_gaa(b, a)) → FOLD_IN_GGA(a, []) at position [] and matcher [ ]

FOLD_IN_GGA(a, [])U2_GGA(a, [], head_out_ga)
with rule FOLD_IN_GGA(a, []) → U2_GGA(a, [], head_out_ga)

Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence


All these steps are and every following step will be a correct step w.r.t to Q.



(96) FALSE