Left Termination of the query pattern
mult_in_3(g, g, a)
w.r.t. the given Prolog program could successfully be proven:
↳ Prolog
↳ PrologToPiTRSProof
Clauses:
mult(0, Y, 0).
mult(s(X), Y, Z) :- ','(mult(X, Y, Z1), add(Z1, Y, Z)).
add(0, Y, Y).
add(s(X), Y, s(Z)) :- add(X, Y, Z).
Queries:
mult(g,g,a).
We use the technique of [30].Transforming Prolog into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
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:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
Using Dependency Pairs [1,30] we result in the following initial DP problem:
Pi DP problem:
The TRS P consists of the following rules:
MULT_IN(s(X), Y, Z) → U11(X, Y, Z, mult_in(X, Y, Z1))
MULT_IN(s(X), Y, Z) → MULT_IN(X, Y, Z1)
U11(X, Y, Z, mult_out(X, Y, Z1)) → U21(X, Y, Z, add_in(Z1, Y, Z))
U11(X, Y, Z, mult_out(X, Y, Z1)) → ADD_IN(Z1, Y, Z)
ADD_IN(s(X), Y, s(Z)) → U31(X, Y, Z, add_in(X, Y, Z))
ADD_IN(s(X), Y, s(Z)) → ADD_IN(X, Y, Z)
The TRS R consists of the following rules:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
ADD_IN(x1, x2, x3) = ADD_IN(x1, x2)
U31(x1, x2, x3, x4) = U31(x4)
U21(x1, x2, x3, x4) = U21(x4)
MULT_IN(x1, x2, x3) = MULT_IN(x1, x2)
U11(x1, x2, x3, x4) = U11(x2, 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:
MULT_IN(s(X), Y, Z) → U11(X, Y, Z, mult_in(X, Y, Z1))
MULT_IN(s(X), Y, Z) → MULT_IN(X, Y, Z1)
U11(X, Y, Z, mult_out(X, Y, Z1)) → U21(X, Y, Z, add_in(Z1, Y, Z))
U11(X, Y, Z, mult_out(X, Y, Z1)) → ADD_IN(Z1, Y, Z)
ADD_IN(s(X), Y, s(Z)) → U31(X, Y, Z, add_in(X, Y, Z))
ADD_IN(s(X), Y, s(Z)) → ADD_IN(X, Y, Z)
The TRS R consists of the following rules:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
ADD_IN(x1, x2, x3) = ADD_IN(x1, x2)
U31(x1, x2, x3, x4) = U31(x4)
U21(x1, x2, x3, x4) = U21(x4)
MULT_IN(x1, x2, x3) = MULT_IN(x1, x2)
U11(x1, x2, x3, x4) = U11(x2, x4)
We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph [30] contains 2 SCCs with 4 less nodes.
↳ Prolog
↳ PrologToPiTRSProof
↳ PiTRS
↳ DependencyPairsProof
↳ PiDP
↳ DependencyGraphProof
↳ AND
↳ PiDP
↳ UsableRulesProof
↳ PiDP
Pi DP problem:
The TRS P consists of the following rules:
ADD_IN(s(X), Y, s(Z)) → ADD_IN(X, Y, Z)
The TRS R consists of the following rules:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
ADD_IN(x1, x2, x3) = ADD_IN(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:
ADD_IN(s(X), Y, s(Z)) → ADD_IN(X, Y, Z)
R is empty.
The argument filtering Pi contains the following mapping:
s(x1) = s(x1)
ADD_IN(x1, x2, x3) = ADD_IN(x1, x2)
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:
ADD_IN(s(X), Y) → ADD_IN(X, Y)
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:
- ADD_IN(s(X), Y) → ADD_IN(X, Y)
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:
MULT_IN(s(X), Y, Z) → MULT_IN(X, Y, Z1)
The TRS R consists of the following rules:
mult_in(s(X), Y, Z) → U1(X, Y, Z, mult_in(X, Y, Z1))
mult_in(0, Y, 0) → mult_out(0, Y, 0)
U1(X, Y, Z, mult_out(X, Y, Z1)) → U2(X, Y, Z, add_in(Z1, Y, Z))
add_in(s(X), Y, s(Z)) → U3(X, Y, Z, add_in(X, Y, Z))
add_in(0, Y, Y) → add_out(0, Y, Y)
U3(X, Y, Z, add_out(X, Y, Z)) → add_out(s(X), Y, s(Z))
U2(X, Y, Z, add_out(Z1, Y, Z)) → mult_out(s(X), Y, Z)
The argument filtering Pi contains the following mapping:
mult_in(x1, x2, x3) = mult_in(x1, x2)
s(x1) = s(x1)
U1(x1, x2, x3, x4) = U1(x2, x4)
0 = 0
mult_out(x1, x2, x3) = mult_out(x3)
U2(x1, x2, x3, x4) = U2(x4)
add_in(x1, x2, x3) = add_in(x1, x2)
U3(x1, x2, x3, x4) = U3(x4)
add_out(x1, x2, x3) = add_out(x3)
MULT_IN(x1, x2, x3) = MULT_IN(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
↳ PiDP
↳ UsableRulesProof
↳ PiDP
↳ PiDPToQDPProof
Pi DP problem:
The TRS P consists of the following rules:
MULT_IN(s(X), Y, Z) → MULT_IN(X, Y, Z1)
R is empty.
The argument filtering Pi contains the following mapping:
s(x1) = s(x1)
MULT_IN(x1, x2, x3) = MULT_IN(x1, x2)
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:
MULT_IN(s(X), Y) → MULT_IN(X, Y)
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:
- MULT_IN(s(X), Y) → MULT_IN(X, Y)
The graph contains the following edges 1 > 1, 2 >= 2