(0) Obligation:
Clauses:
bin_tree(void) :- !.
bin_tree(T) :- ','(left(T, L), ','(right(T, R), ','(bin_tree(L), bin_tree(R)))).
left(void, void).
left(tree(X1, L, X2), L).
right(void, void).
right(tree(X3, X4, R), R).
Query: bin_tree(g)
(1) PrologToPrologProblemTransformerProof (SOUND transformation)
Built Prolog problem from termination graph ICLP10.
(2) Obligation:
Clauses:
bin_treeA(void).
bin_treeA(tree(T19, T20, T21)) :- bin_treeA(T20).
bin_treeA(tree(T19, T20, T21)) :- ','(bin_treeA(T20), bin_treeA(T21)).
Query: bin_treeA(g)
(3) PrologToPiTRSProof (SOUND transformation)
We use the technique of [TOCL09]. With regard to the inferred argument filtering the predicates were used in the following modes:
bin_treeA_in: (b)
Transforming
Prolog into the following
Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:
bin_treeA_in_g(void) → bin_treeA_out_g(void)
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T19, T20, T21, bin_treeA_in_g(T20))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → bin_treeA_out_g(tree(T19, T20, T21))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → U2_g(T19, T20, T21, bin_treeA_in_g(T21))
U2_g(T19, T20, T21, bin_treeA_out_g(T21)) → bin_treeA_out_g(tree(T19, T20, T21))
The argument filtering Pi contains the following mapping:
bin_treeA_in_g(
x1) =
bin_treeA_in_g(
x1)
void =
void
bin_treeA_out_g(
x1) =
bin_treeA_out_g
tree(
x1,
x2,
x3) =
tree(
x1,
x2,
x3)
U1_g(
x1,
x2,
x3,
x4) =
U1_g(
x3,
x4)
U2_g(
x1,
x2,
x3,
x4) =
U2_g(
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:
bin_treeA_in_g(void) → bin_treeA_out_g(void)
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T19, T20, T21, bin_treeA_in_g(T20))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → bin_treeA_out_g(tree(T19, T20, T21))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → U2_g(T19, T20, T21, bin_treeA_in_g(T21))
U2_g(T19, T20, T21, bin_treeA_out_g(T21)) → bin_treeA_out_g(tree(T19, T20, T21))
The argument filtering Pi contains the following mapping:
bin_treeA_in_g(
x1) =
bin_treeA_in_g(
x1)
void =
void
bin_treeA_out_g(
x1) =
bin_treeA_out_g
tree(
x1,
x2,
x3) =
tree(
x1,
x2,
x3)
U1_g(
x1,
x2,
x3,
x4) =
U1_g(
x3,
x4)
U2_g(
x1,
x2,
x3,
x4) =
U2_g(
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:
BIN_TREEA_IN_G(tree(T19, T20, T21)) → U1_G(T19, T20, T21, bin_treeA_in_g(T20))
BIN_TREEA_IN_G(tree(T19, T20, T21)) → BIN_TREEA_IN_G(T20)
U1_G(T19, T20, T21, bin_treeA_out_g(T20)) → U2_G(T19, T20, T21, bin_treeA_in_g(T21))
U1_G(T19, T20, T21, bin_treeA_out_g(T20)) → BIN_TREEA_IN_G(T21)
The TRS R consists of the following rules:
bin_treeA_in_g(void) → bin_treeA_out_g(void)
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T19, T20, T21, bin_treeA_in_g(T20))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → bin_treeA_out_g(tree(T19, T20, T21))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → U2_g(T19, T20, T21, bin_treeA_in_g(T21))
U2_g(T19, T20, T21, bin_treeA_out_g(T21)) → bin_treeA_out_g(tree(T19, T20, T21))
The argument filtering Pi contains the following mapping:
bin_treeA_in_g(
x1) =
bin_treeA_in_g(
x1)
void =
void
bin_treeA_out_g(
x1) =
bin_treeA_out_g
tree(
x1,
x2,
x3) =
tree(
x1,
x2,
x3)
U1_g(
x1,
x2,
x3,
x4) =
U1_g(
x3,
x4)
U2_g(
x1,
x2,
x3,
x4) =
U2_g(
x4)
BIN_TREEA_IN_G(
x1) =
BIN_TREEA_IN_G(
x1)
U1_G(
x1,
x2,
x3,
x4) =
U1_G(
x3,
x4)
U2_G(
x1,
x2,
x3,
x4) =
U2_G(
x4)
We have to consider all (P,R,Pi)-chains
(6) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
BIN_TREEA_IN_G(tree(T19, T20, T21)) → U1_G(T19, T20, T21, bin_treeA_in_g(T20))
BIN_TREEA_IN_G(tree(T19, T20, T21)) → BIN_TREEA_IN_G(T20)
U1_G(T19, T20, T21, bin_treeA_out_g(T20)) → U2_G(T19, T20, T21, bin_treeA_in_g(T21))
U1_G(T19, T20, T21, bin_treeA_out_g(T20)) → BIN_TREEA_IN_G(T21)
The TRS R consists of the following rules:
bin_treeA_in_g(void) → bin_treeA_out_g(void)
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T19, T20, T21, bin_treeA_in_g(T20))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → bin_treeA_out_g(tree(T19, T20, T21))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → U2_g(T19, T20, T21, bin_treeA_in_g(T21))
U2_g(T19, T20, T21, bin_treeA_out_g(T21)) → bin_treeA_out_g(tree(T19, T20, T21))
The argument filtering Pi contains the following mapping:
bin_treeA_in_g(
x1) =
bin_treeA_in_g(
x1)
void =
void
bin_treeA_out_g(
x1) =
bin_treeA_out_g
tree(
x1,
x2,
x3) =
tree(
x1,
x2,
x3)
U1_g(
x1,
x2,
x3,
x4) =
U1_g(
x3,
x4)
U2_g(
x1,
x2,
x3,
x4) =
U2_g(
x4)
BIN_TREEA_IN_G(
x1) =
BIN_TREEA_IN_G(
x1)
U1_G(
x1,
x2,
x3,
x4) =
U1_G(
x3,
x4)
U2_G(
x1,
x2,
x3,
x4) =
U2_G(
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 1 less node.
(8) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
U1_G(T19, T20, T21, bin_treeA_out_g(T20)) → BIN_TREEA_IN_G(T21)
BIN_TREEA_IN_G(tree(T19, T20, T21)) → U1_G(T19, T20, T21, bin_treeA_in_g(T20))
BIN_TREEA_IN_G(tree(T19, T20, T21)) → BIN_TREEA_IN_G(T20)
The TRS R consists of the following rules:
bin_treeA_in_g(void) → bin_treeA_out_g(void)
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T19, T20, T21, bin_treeA_in_g(T20))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → bin_treeA_out_g(tree(T19, T20, T21))
U1_g(T19, T20, T21, bin_treeA_out_g(T20)) → U2_g(T19, T20, T21, bin_treeA_in_g(T21))
U2_g(T19, T20, T21, bin_treeA_out_g(T21)) → bin_treeA_out_g(tree(T19, T20, T21))
The argument filtering Pi contains the following mapping:
bin_treeA_in_g(
x1) =
bin_treeA_in_g(
x1)
void =
void
bin_treeA_out_g(
x1) =
bin_treeA_out_g
tree(
x1,
x2,
x3) =
tree(
x1,
x2,
x3)
U1_g(
x1,
x2,
x3,
x4) =
U1_g(
x3,
x4)
U2_g(
x1,
x2,
x3,
x4) =
U2_g(
x4)
BIN_TREEA_IN_G(
x1) =
BIN_TREEA_IN_G(
x1)
U1_G(
x1,
x2,
x3,
x4) =
U1_G(
x3,
x4)
We have to consider all (P,R,Pi)-chains
(9) PiDPToQDPProof (SOUND transformation)
Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.
(10) Obligation:
Q DP problem:
The TRS P consists of the following rules:
U1_G(T21, bin_treeA_out_g) → BIN_TREEA_IN_G(T21)
BIN_TREEA_IN_G(tree(T19, T20, T21)) → U1_G(T21, bin_treeA_in_g(T20))
BIN_TREEA_IN_G(tree(T19, T20, T21)) → BIN_TREEA_IN_G(T20)
The TRS R consists of the following rules:
bin_treeA_in_g(void) → bin_treeA_out_g
bin_treeA_in_g(tree(T19, T20, T21)) → U1_g(T21, bin_treeA_in_g(T20))
U1_g(T21, bin_treeA_out_g) → bin_treeA_out_g
U1_g(T21, bin_treeA_out_g) → U2_g(bin_treeA_in_g(T21))
U2_g(bin_treeA_out_g) → bin_treeA_out_g
The set Q consists of the following terms:
bin_treeA_in_g(x0)
U1_g(x0, x1)
U2_g(x0)
We have to consider all (P,Q,R)-chains.
(11) 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:
- BIN_TREEA_IN_G(tree(T19, T20, T21)) → U1_G(T21, bin_treeA_in_g(T20))
The graph contains the following edges 1 > 1
- BIN_TREEA_IN_G(tree(T19, T20, T21)) → BIN_TREEA_IN_G(T20)
The graph contains the following edges 1 > 1
- U1_G(T21, bin_treeA_out_g) → BIN_TREEA_IN_G(T21)
The graph contains the following edges 1 >= 1
(12) YES