(0) Obligation:
Clauses:
less(0, s(X2)).
less(X, Y) :- ','(no(zero(X)), ','(p(X, X1), ','(p(Y, Y1), less(X1, Y1)))).
p(0, 0).
p(s(X), X).
zero(0).
no(X) :- ','(X, ','(!, failure(a))).
no(X3).
failure(b).
Query: less(g,a)
(1) PrologToPiTRSViaGraphTransformerProof (SOUND transformation)
Transformed Prolog program to (Pi-)TRS.
(2) Obligation:
Pi-finite rewrite system:
The TRS R consists of the following rules:
lessA_in_ga(0, s(T4)) → lessA_out_ga(0, s(T4))
lessA_in_ga(s(T21), 0) → U1_ga(T21, lessB_in_g(T21))
lessB_in_g(s(T33)) → U3_g(T33, lessB_in_g(T33))
U3_g(T33, lessB_out_g(T33)) → lessB_out_g(s(T33))
U1_ga(T21, lessB_out_g(T21)) → lessA_out_ga(s(T21), 0)
lessA_in_ga(s(T21), s(T37)) → U2_ga(T21, T37, lessA_in_ga(T21, T37))
U2_ga(T21, T37, lessA_out_ga(T21, T37)) → lessA_out_ga(s(T21), s(T37))
The argument filtering Pi contains the following mapping:
lessA_in_ga(
x1,
x2) =
lessA_in_ga(
x1)
0 =
0
lessA_out_ga(
x1,
x2) =
lessA_out_ga(
x1)
s(
x1) =
s(
x1)
U1_ga(
x1,
x2) =
U1_ga(
x1,
x2)
lessB_in_g(
x1) =
lessB_in_g(
x1)
U3_g(
x1,
x2) =
U3_g(
x1,
x2)
lessB_out_g(
x1) =
lessB_out_g(
x1)
U2_ga(
x1,
x2,
x3) =
U2_ga(
x1,
x3)
(3) 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:
LESSA_IN_GA(s(T21), 0) → U1_GA(T21, lessB_in_g(T21))
LESSA_IN_GA(s(T21), 0) → LESSB_IN_G(T21)
LESSB_IN_G(s(T33)) → U3_G(T33, lessB_in_g(T33))
LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
LESSA_IN_GA(s(T21), s(T37)) → U2_GA(T21, T37, lessA_in_ga(T21, T37))
LESSA_IN_GA(s(T21), s(T37)) → LESSA_IN_GA(T21, T37)
The TRS R consists of the following rules:
lessA_in_ga(0, s(T4)) → lessA_out_ga(0, s(T4))
lessA_in_ga(s(T21), 0) → U1_ga(T21, lessB_in_g(T21))
lessB_in_g(s(T33)) → U3_g(T33, lessB_in_g(T33))
U3_g(T33, lessB_out_g(T33)) → lessB_out_g(s(T33))
U1_ga(T21, lessB_out_g(T21)) → lessA_out_ga(s(T21), 0)
lessA_in_ga(s(T21), s(T37)) → U2_ga(T21, T37, lessA_in_ga(T21, T37))
U2_ga(T21, T37, lessA_out_ga(T21, T37)) → lessA_out_ga(s(T21), s(T37))
The argument filtering Pi contains the following mapping:
lessA_in_ga(
x1,
x2) =
lessA_in_ga(
x1)
0 =
0
lessA_out_ga(
x1,
x2) =
lessA_out_ga(
x1)
s(
x1) =
s(
x1)
U1_ga(
x1,
x2) =
U1_ga(
x1,
x2)
lessB_in_g(
x1) =
lessB_in_g(
x1)
U3_g(
x1,
x2) =
U3_g(
x1,
x2)
lessB_out_g(
x1) =
lessB_out_g(
x1)
U2_ga(
x1,
x2,
x3) =
U2_ga(
x1,
x3)
LESSA_IN_GA(
x1,
x2) =
LESSA_IN_GA(
x1)
U1_GA(
x1,
x2) =
U1_GA(
x1,
x2)
LESSB_IN_G(
x1) =
LESSB_IN_G(
x1)
U3_G(
x1,
x2) =
U3_G(
x1,
x2)
U2_GA(
x1,
x2,
x3) =
U2_GA(
x1,
x3)
We have to consider all (P,R,Pi)-chains
(4) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
LESSA_IN_GA(s(T21), 0) → U1_GA(T21, lessB_in_g(T21))
LESSA_IN_GA(s(T21), 0) → LESSB_IN_G(T21)
LESSB_IN_G(s(T33)) → U3_G(T33, lessB_in_g(T33))
LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
LESSA_IN_GA(s(T21), s(T37)) → U2_GA(T21, T37, lessA_in_ga(T21, T37))
LESSA_IN_GA(s(T21), s(T37)) → LESSA_IN_GA(T21, T37)
The TRS R consists of the following rules:
lessA_in_ga(0, s(T4)) → lessA_out_ga(0, s(T4))
lessA_in_ga(s(T21), 0) → U1_ga(T21, lessB_in_g(T21))
lessB_in_g(s(T33)) → U3_g(T33, lessB_in_g(T33))
U3_g(T33, lessB_out_g(T33)) → lessB_out_g(s(T33))
U1_ga(T21, lessB_out_g(T21)) → lessA_out_ga(s(T21), 0)
lessA_in_ga(s(T21), s(T37)) → U2_ga(T21, T37, lessA_in_ga(T21, T37))
U2_ga(T21, T37, lessA_out_ga(T21, T37)) → lessA_out_ga(s(T21), s(T37))
The argument filtering Pi contains the following mapping:
lessA_in_ga(
x1,
x2) =
lessA_in_ga(
x1)
0 =
0
lessA_out_ga(
x1,
x2) =
lessA_out_ga(
x1)
s(
x1) =
s(
x1)
U1_ga(
x1,
x2) =
U1_ga(
x1,
x2)
lessB_in_g(
x1) =
lessB_in_g(
x1)
U3_g(
x1,
x2) =
U3_g(
x1,
x2)
lessB_out_g(
x1) =
lessB_out_g(
x1)
U2_ga(
x1,
x2,
x3) =
U2_ga(
x1,
x3)
LESSA_IN_GA(
x1,
x2) =
LESSA_IN_GA(
x1)
U1_GA(
x1,
x2) =
U1_GA(
x1,
x2)
LESSB_IN_G(
x1) =
LESSB_IN_G(
x1)
U3_G(
x1,
x2) =
U3_G(
x1,
x2)
U2_GA(
x1,
x2,
x3) =
U2_GA(
x1,
x3)
We have to consider all (P,R,Pi)-chains
(5) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LOPSTR] contains 2 SCCs with 4 less nodes.
(6) Complex Obligation (AND)
(7) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
The TRS R consists of the following rules:
lessA_in_ga(0, s(T4)) → lessA_out_ga(0, s(T4))
lessA_in_ga(s(T21), 0) → U1_ga(T21, lessB_in_g(T21))
lessB_in_g(s(T33)) → U3_g(T33, lessB_in_g(T33))
U3_g(T33, lessB_out_g(T33)) → lessB_out_g(s(T33))
U1_ga(T21, lessB_out_g(T21)) → lessA_out_ga(s(T21), 0)
lessA_in_ga(s(T21), s(T37)) → U2_ga(T21, T37, lessA_in_ga(T21, T37))
U2_ga(T21, T37, lessA_out_ga(T21, T37)) → lessA_out_ga(s(T21), s(T37))
The argument filtering Pi contains the following mapping:
lessA_in_ga(
x1,
x2) =
lessA_in_ga(
x1)
0 =
0
lessA_out_ga(
x1,
x2) =
lessA_out_ga(
x1)
s(
x1) =
s(
x1)
U1_ga(
x1,
x2) =
U1_ga(
x1,
x2)
lessB_in_g(
x1) =
lessB_in_g(
x1)
U3_g(
x1,
x2) =
U3_g(
x1,
x2)
lessB_out_g(
x1) =
lessB_out_g(
x1)
U2_ga(
x1,
x2,
x3) =
U2_ga(
x1,
x3)
LESSB_IN_G(
x1) =
LESSB_IN_G(
x1)
We have to consider all (P,R,Pi)-chains
(8) UsableRulesProof (EQUIVALENT transformation)
For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.
(9) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains
(10) PiDPToQDPProof (EQUIVALENT transformation)
Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.
(11) Obligation:
Q DP problem:
The TRS P consists of the following rules:
LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
(12) 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:
- LESSB_IN_G(s(T33)) → LESSB_IN_G(T33)
The graph contains the following edges 1 > 1
(13) YES
(14) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
LESSA_IN_GA(s(T21), s(T37)) → LESSA_IN_GA(T21, T37)
The TRS R consists of the following rules:
lessA_in_ga(0, s(T4)) → lessA_out_ga(0, s(T4))
lessA_in_ga(s(T21), 0) → U1_ga(T21, lessB_in_g(T21))
lessB_in_g(s(T33)) → U3_g(T33, lessB_in_g(T33))
U3_g(T33, lessB_out_g(T33)) → lessB_out_g(s(T33))
U1_ga(T21, lessB_out_g(T21)) → lessA_out_ga(s(T21), 0)
lessA_in_ga(s(T21), s(T37)) → U2_ga(T21, T37, lessA_in_ga(T21, T37))
U2_ga(T21, T37, lessA_out_ga(T21, T37)) → lessA_out_ga(s(T21), s(T37))
The argument filtering Pi contains the following mapping:
lessA_in_ga(
x1,
x2) =
lessA_in_ga(
x1)
0 =
0
lessA_out_ga(
x1,
x2) =
lessA_out_ga(
x1)
s(
x1) =
s(
x1)
U1_ga(
x1,
x2) =
U1_ga(
x1,
x2)
lessB_in_g(
x1) =
lessB_in_g(
x1)
U3_g(
x1,
x2) =
U3_g(
x1,
x2)
lessB_out_g(
x1) =
lessB_out_g(
x1)
U2_ga(
x1,
x2,
x3) =
U2_ga(
x1,
x3)
LESSA_IN_GA(
x1,
x2) =
LESSA_IN_GA(
x1)
We have to consider all (P,R,Pi)-chains
(15) UsableRulesProof (EQUIVALENT transformation)
For (infinitary) constructor rewriting [LOPSTR] we can delete all non-usable rules from R.
(16) Obligation:
Pi DP problem:
The TRS P consists of the following rules:
LESSA_IN_GA(s(T21), s(T37)) → LESSA_IN_GA(T21, T37)
R is empty.
The argument filtering Pi contains the following mapping:
s(
x1) =
s(
x1)
LESSA_IN_GA(
x1,
x2) =
LESSA_IN_GA(
x1)
We have to consider all (P,R,Pi)-chains
(17) PiDPToQDPProof (SOUND transformation)
Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.
(18) Obligation:
Q DP problem:
The TRS P consists of the following rules:
LESSA_IN_GA(s(T21)) → LESSA_IN_GA(T21)
R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
(19) 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:
- LESSA_IN_GA(s(T21)) → LESSA_IN_GA(T21)
The graph contains the following edges 1 > 1
(20) YES