Left Termination of the query pattern
bin_tree_in_1(g)
w.r.t. the given Prolog program could successfully be proven:
↳ Prolog
↳ PrologToPiTRSProof
Clauses:
bin_tree(void).
bin_tree(tree(X, Left, Right)) :- ','(bin_tree(Left), bin_tree(Right)).
Queries:
bin_tree(g).
We use the technique of [30]. With regard to the inferred argument filtering the predicates were used in the following modes:
bin_tree_in: (b)
Transforming Prolog into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g(void)
bin_tree_in_g(tree(X, Left, Right)) → U1_g(X, Left, Right, bin_tree_in_g(Left))
U1_g(X, Left, Right, bin_tree_out_g(Left)) → U2_g(X, Left, Right, bin_tree_in_g(Right))
U2_g(X, Left, Right, bin_tree_out_g(Right)) → bin_tree_out_g(tree(X, Left, Right))
The argument filtering Pi contains the following mapping:
bin_tree_in_g(x1) = bin_tree_in_g(x1)
void = void
bin_tree_out_g(x1) = bin_tree_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
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
Pi-finite rewrite system:
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g(void)
bin_tree_in_g(tree(X, Left, Right)) → U1_g(X, Left, Right, bin_tree_in_g(Left))
U1_g(X, Left, Right, bin_tree_out_g(Left)) → U2_g(X, Left, Right, bin_tree_in_g(Right))
U2_g(X, Left, Right, bin_tree_out_g(Right)) → bin_tree_out_g(tree(X, Left, Right))
The argument filtering Pi contains the following mapping:
bin_tree_in_g(x1) = bin_tree_in_g(x1)
void = void
bin_tree_out_g(x1) = bin_tree_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)
Using Dependency Pairs [1,30] we result in the following initial DP problem:
Pi DP problem:
The TRS P consists of the following rules:
BIN_TREE_IN_G(tree(X, Left, Right)) → U1_G(X, Left, Right, bin_tree_in_g(Left))
BIN_TREE_IN_G(tree(X, Left, Right)) → BIN_TREE_IN_G(Left)
U1_G(X, Left, Right, bin_tree_out_g(Left)) → U2_G(X, Left, Right, bin_tree_in_g(Right))
U1_G(X, Left, Right, bin_tree_out_g(Left)) → BIN_TREE_IN_G(Right)
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g(void)
bin_tree_in_g(tree(X, Left, Right)) → U1_g(X, Left, Right, bin_tree_in_g(Left))
U1_g(X, Left, Right, bin_tree_out_g(Left)) → U2_g(X, Left, Right, bin_tree_in_g(Right))
U2_g(X, Left, Right, bin_tree_out_g(Right)) → bin_tree_out_g(tree(X, Left, Right))
The argument filtering Pi contains the following mapping:
bin_tree_in_g(x1) = bin_tree_in_g(x1)
void = void
bin_tree_out_g(x1) = bin_tree_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)
U1_G(x1, x2, x3, x4) = U1_G(x3, x4)
BIN_TREE_IN_G(x1) = BIN_TREE_IN_G(x1)
U2_G(x1, x2, x3, x4) = U2_G(x4)
We have to consider all (P,R,Pi)-chains
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
Pi DP problem:
The TRS P consists of the following rules:
BIN_TREE_IN_G(tree(X, Left, Right)) → U1_G(X, Left, Right, bin_tree_in_g(Left))
BIN_TREE_IN_G(tree(X, Left, Right)) → BIN_TREE_IN_G(Left)
U1_G(X, Left, Right, bin_tree_out_g(Left)) → U2_G(X, Left, Right, bin_tree_in_g(Right))
U1_G(X, Left, Right, bin_tree_out_g(Left)) → BIN_TREE_IN_G(Right)
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g(void)
bin_tree_in_g(tree(X, Left, Right)) → U1_g(X, Left, Right, bin_tree_in_g(Left))
U1_g(X, Left, Right, bin_tree_out_g(Left)) → U2_g(X, Left, Right, bin_tree_in_g(Right))
U2_g(X, Left, Right, bin_tree_out_g(Right)) → bin_tree_out_g(tree(X, Left, Right))
The argument filtering Pi contains the following mapping:
bin_tree_in_g(x1) = bin_tree_in_g(x1)
void = void
bin_tree_out_g(x1) = bin_tree_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)
U1_G(x1, x2, x3, x4) = U1_G(x3, x4)
BIN_TREE_IN_G(x1) = BIN_TREE_IN_G(x1)
U2_G(x1, x2, x3, x4) = U2_G(x4)
We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph [30] contains 1 SCC with 1 less node.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ PiDP
↳ PiDPToQDPProof
Pi DP problem:
The TRS P consists of the following rules:
U1_G(X, Left, Right, bin_tree_out_g(Left)) → BIN_TREE_IN_G(Right)
BIN_TREE_IN_G(tree(X, Left, Right)) → BIN_TREE_IN_G(Left)
BIN_TREE_IN_G(tree(X, Left, Right)) → U1_G(X, Left, Right, bin_tree_in_g(Left))
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g(void)
bin_tree_in_g(tree(X, Left, Right)) → U1_g(X, Left, Right, bin_tree_in_g(Left))
U1_g(X, Left, Right, bin_tree_out_g(Left)) → U2_g(X, Left, Right, bin_tree_in_g(Right))
U2_g(X, Left, Right, bin_tree_out_g(Right)) → bin_tree_out_g(tree(X, Left, Right))
The argument filtering Pi contains the following mapping:
bin_tree_in_g(x1) = bin_tree_in_g(x1)
void = void
bin_tree_out_g(x1) = bin_tree_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)
U1_G(x1, x2, x3, x4) = U1_G(x3, x4)
BIN_TREE_IN_G(x1) = BIN_TREE_IN_G(x1)
We have to consider all (P,R,Pi)-chains
Transforming (infinitary) constructor rewriting Pi-DP problem [30] into ordinary QDP problem [15] by application of Pi.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ PiDP
↳ PiDPToQDPProof
↳ QDP
↳ QDPSizeChangeProof
Q DP problem:
The TRS P consists of the following rules:
U1_G(Right, bin_tree_out_g) → BIN_TREE_IN_G(Right)
BIN_TREE_IN_G(tree(X, Left, Right)) → BIN_TREE_IN_G(Left)
BIN_TREE_IN_G(tree(X, Left, Right)) → U1_G(Right, bin_tree_in_g(Left))
The TRS R consists of the following rules:
bin_tree_in_g(void) → bin_tree_out_g
bin_tree_in_g(tree(X, Left, Right)) → U1_g(Right, bin_tree_in_g(Left))
U1_g(Right, bin_tree_out_g) → U2_g(bin_tree_in_g(Right))
U2_g(bin_tree_out_g) → bin_tree_out_g
The set Q consists of the following terms:
bin_tree_in_g(x0)
U1_g(x0, x1)
U2_g(x0)
We have to consider all (P,Q,R)-chains.
By using the subterm criterion [20] together with the size-change analysis [32] 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_TREE_IN_G(tree(X, Left, Right)) → U1_G(Right, bin_tree_in_g(Left))
The graph contains the following edges 1 > 1
- BIN_TREE_IN_G(tree(X, Left, Right)) → BIN_TREE_IN_G(Left)
The graph contains the following edges 1 > 1
- U1_G(Right, bin_tree_out_g) → BIN_TREE_IN_G(Right)
The graph contains the following edges 1 >= 1