Left Termination of the query pattern
subset_in_2(g, g)
w.r.t. the given Prolog program could successfully be proven:
↳ Prolog
↳ PrologToPiTRSProof
Clauses:
member(X, .(Y, Xs)) :- member(X, Xs).
member(X, .(X, Xs)).
subset(.(X, Xs), Ys) :- ','(member(X, Ys), subset(Xs, Ys)).
subset([], Ys).
Queries:
subset(g,g).
We use the technique of [30]. With regard to the inferred argument filtering the predicates were used in the following modes:
subset_in: (b,b)
member_in: (b,b)
Transforming Prolog into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
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:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
Using Dependency Pairs [1,30] we result in the following initial DP problem:
Pi DP problem:
The TRS P consists of the following rules:
SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(X, Xs, Ys, member_in_gg(X, Ys))
SUBSET_IN_GG(.(X, Xs), Ys) → MEMBER_IN_GG(X, Ys)
MEMBER_IN_GG(X, .(Y, Xs)) → U1_GG(X, Y, Xs, member_in_gg(X, Xs))
MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → U3_GG(X, Xs, Ys, subset_in_gg(Xs, Ys))
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → SUBSET_IN_GG(Xs, Ys)
The TRS R consists of the following rules:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
U1_GG(x1, x2, x3, x4) = U1_GG(x4)
MEMBER_IN_GG(x1, x2) = MEMBER_IN_GG(x1, x2)
SUBSET_IN_GG(x1, x2) = SUBSET_IN_GG(x1, x2)
U2_GG(x1, x2, x3, x4) = U2_GG(x2, x3, x4)
U3_GG(x1, x2, x3, x4) = U3_GG(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:
SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(X, Xs, Ys, member_in_gg(X, Ys))
SUBSET_IN_GG(.(X, Xs), Ys) → MEMBER_IN_GG(X, Ys)
MEMBER_IN_GG(X, .(Y, Xs)) → U1_GG(X, Y, Xs, member_in_gg(X, Xs))
MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → U3_GG(X, Xs, Ys, subset_in_gg(Xs, Ys))
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → SUBSET_IN_GG(Xs, Ys)
The TRS R consists of the following rules:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
U1_GG(x1, x2, x3, x4) = U1_GG(x4)
MEMBER_IN_GG(x1, x2) = MEMBER_IN_GG(x1, x2)
SUBSET_IN_GG(x1, x2) = SUBSET_IN_GG(x1, x2)
U2_GG(x1, x2, x3, x4) = U2_GG(x2, x3, x4)
U3_GG(x1, x2, x3, x4) = U3_GG(x4)
We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph [30] contains 2 SCCs with 3 less nodes.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ AND
↳ PiDP
↳ UsableRulesProof
↳ PiDP
Pi DP problem:
The TRS P consists of the following rules:
MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
The TRS R consists of the following rules:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
MEMBER_IN_GG(x1, x2) = MEMBER_IN_GG(x1, x2)
We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting [30] we can delete all non-usable rules from R.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ AND
↳ PiDP
↳ UsableRulesProof
↳ PiDP
↳ PiDPToQDPProof
↳ PiDP
Pi DP problem:
The TRS P consists of the following rules:
MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
R is empty.
Pi is empty.
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
↳ AND
↳ PiDP
↳ UsableRulesProof
↳ PiDP
↳ PiDPToQDPProof
↳ QDP
↳ QDPSizeChangeProof
↳ PiDP
Q DP problem:
The TRS P consists of the following rules:
MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
R is empty.
Q is empty.
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:
- MEMBER_IN_GG(X, .(Y, Xs)) → MEMBER_IN_GG(X, Xs)
The graph contains the following edges 1 >= 1, 2 > 2
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ AND
↳ PiDP
↳ PiDP
↳ UsableRulesProof
Pi DP problem:
The TRS P consists of the following rules:
SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(X, Xs, Ys, member_in_gg(X, Ys))
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → SUBSET_IN_GG(Xs, Ys)
The TRS R consists of the following rules:
subset_in_gg(.(X, Xs), Ys) → U2_gg(X, Xs, Ys, member_in_gg(X, Ys))
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
U2_gg(X, Xs, Ys, member_out_gg(X, Ys)) → U3_gg(X, Xs, Ys, subset_in_gg(Xs, Ys))
subset_in_gg([], Ys) → subset_out_gg([], Ys)
U3_gg(X, Xs, Ys, subset_out_gg(Xs, Ys)) → subset_out_gg(.(X, Xs), Ys)
The argument filtering Pi contains the following mapping:
subset_in_gg(x1, x2) = subset_in_gg(x1, x2)
.(x1, x2) = .(x1, x2)
U2_gg(x1, x2, x3, x4) = U2_gg(x2, x3, x4)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
U3_gg(x1, x2, x3, x4) = U3_gg(x4)
[] = []
subset_out_gg(x1, x2) = subset_out_gg
SUBSET_IN_GG(x1, x2) = SUBSET_IN_GG(x1, x2)
U2_GG(x1, x2, x3, x4) = U2_GG(x2, x3, x4)
We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting [30] we can delete all non-usable rules from R.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ AND
↳ PiDP
↳ PiDP
↳ UsableRulesProof
↳ PiDP
↳ PiDPToQDPProof
Pi DP problem:
The TRS P consists of the following rules:
SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(X, Xs, Ys, member_in_gg(X, Ys))
U2_GG(X, Xs, Ys, member_out_gg(X, Ys)) → SUBSET_IN_GG(Xs, Ys)
The TRS R consists of the following rules:
member_in_gg(X, .(Y, Xs)) → U1_gg(X, Y, Xs, member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg(X, .(X, Xs))
U1_gg(X, Y, Xs, member_out_gg(X, Xs)) → member_out_gg(X, .(Y, Xs))
The argument filtering Pi contains the following mapping:
.(x1, x2) = .(x1, x2)
member_in_gg(x1, x2) = member_in_gg(x1, x2)
U1_gg(x1, x2, x3, x4) = U1_gg(x4)
member_out_gg(x1, x2) = member_out_gg
SUBSET_IN_GG(x1, x2) = SUBSET_IN_GG(x1, x2)
U2_GG(x1, x2, x3, x4) = U2_GG(x2, x3, x4)
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
↳ AND
↳ PiDP
↳ PiDP
↳ UsableRulesProof
↳ PiDP
↳ PiDPToQDPProof
↳ QDP
↳ QDPSizeChangeProof
Q DP problem:
The TRS P consists of the following rules:
U2_GG(Xs, Ys, member_out_gg) → SUBSET_IN_GG(Xs, Ys)
SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(Xs, Ys, member_in_gg(X, Ys))
The TRS R consists of the following rules:
member_in_gg(X, .(Y, Xs)) → U1_gg(member_in_gg(X, Xs))
member_in_gg(X, .(X, Xs)) → member_out_gg
U1_gg(member_out_gg) → member_out_gg
The set Q consists of the following terms:
member_in_gg(x0, x1)
U1_gg(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:
- U2_GG(Xs, Ys, member_out_gg) → SUBSET_IN_GG(Xs, Ys)
The graph contains the following edges 1 >= 1, 2 >= 2
- SUBSET_IN_GG(.(X, Xs), Ys) → U2_GG(Xs, Ys, member_in_gg(X, Ys))
The graph contains the following edges 1 > 1, 2 >= 2