YES
0 QTRS
↳1 QTRSToCSRProof (⇔, 0 ms)
↳2 CSR
↳3 CSRRRRProof (⇔, 41 ms)
↳4 CSR
↳5 CSRRRRProof (⇔, 0 ms)
↳6 CSR
↳7 CSRRRRProof (⇔, 0 ms)
↳8 CSR
↳9 CSRRRRProof (⇔, 0 ms)
↳10 CSR
↳11 RisEmptyProof (⇔, 0 ms)
↳12 YES
active(from(X)) → mark(cons(X, from(s(X))))
active(length(nil)) → mark(0)
active(length(cons(X, Y))) → mark(s(length1(Y)))
active(length1(X)) → mark(length(X))
active(from(X)) → from(active(X))
active(cons(X1, X2)) → cons(active(X1), X2)
active(s(X)) → s(active(X))
from(mark(X)) → mark(from(X))
cons(mark(X1), X2) → mark(cons(X1, X2))
s(mark(X)) → mark(s(X))
proper(from(X)) → from(proper(X))
proper(cons(X1, X2)) → cons(proper(X1), proper(X2))
proper(s(X)) → s(proper(X))
proper(length(X)) → length(proper(X))
proper(nil) → ok(nil)
proper(0) → ok(0)
proper(length1(X)) → length1(proper(X))
from(ok(X)) → ok(from(X))
cons(ok(X1), ok(X2)) → ok(cons(X1, X2))
s(ok(X)) → ok(s(X))
length(ok(X)) → ok(length(X))
length1(ok(X)) → ok(length1(X))
top(mark(X)) → top(proper(X))
top(ok(X)) → top(active(X))
active(from(X)) → mark(cons(X, from(s(X))))
active(length(nil)) → mark(0)
active(length(cons(X, Y))) → mark(s(length1(Y)))
active(length1(X)) → mark(length(X))
active(from(X)) → from(active(X))
active(cons(X1, X2)) → cons(active(X1), X2)
active(s(X)) → s(active(X))
from(mark(X)) → mark(from(X))
cons(mark(X1), X2) → mark(cons(X1, X2))
s(mark(X)) → mark(s(X))
proper(from(X)) → from(proper(X))
proper(cons(X1, X2)) → cons(proper(X1), proper(X2))
proper(s(X)) → s(proper(X))
proper(length(X)) → length(proper(X))
proper(nil) → ok(nil)
proper(0) → ok(0)
proper(length1(X)) → length1(proper(X))
from(ok(X)) → ok(from(X))
cons(ok(X1), ok(X2)) → ok(cons(X1, X2))
s(ok(X)) → ok(s(X))
length(ok(X)) → ok(length(X))
length1(ok(X)) → ok(length1(X))
top(mark(X)) → top(proper(X))
top(ok(X)) → top(active(X))
from: {1}
cons: {1}
s: {1}
length: empty set
nil: empty set
0: empty set
length1: empty set
The QTRS contained all rules created by the complete Giesl-Middeldorp transformation. Therefore, the inverse transformation is complete (and sound).
from(X) → cons(X, from(s(X)))
length(nil) → 0
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
from: {1}
cons: {1}
s: {1}
length: empty set
nil: empty set
0: empty set
length1: empty set
from(X) → cons(X, from(s(X)))
length(nil) → 0
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
from: {1}
cons: {1}
s: {1}
length: empty set
nil: empty set
0: empty set
length1: empty set
Used ordering:
Polynomial interpretation [POLO]:
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(0) = 0
POL(cons(x1, x2)) = 1 + 2·x1
POL(from(x1)) = 2 + 2·x1
POL(length(x1)) = 0
POL(length1(x1)) = 0
POL(nil) = 0
POL(s(x1)) = 2·x1
from(X) → cons(X, from(s(X)))
length(nil) → 0
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
cons: {1}
s: {1}
length: empty set
nil: empty set
0: empty set
length1: empty set
length(nil) → 0
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
cons: {1}
s: {1}
length: empty set
nil: empty set
0: empty set
length1: empty set
Used ordering:
Polynomial interpretation [POLO]:
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(0) = 0
POL(cons(x1, x2)) = x1 + x2
POL(length(x1)) = 1 + x1
POL(length1(x1)) = 1 + x1
POL(nil) = 0
POL(s(x1)) = x1
length(nil) → 0
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
cons: {1}
s: {1}
length: empty set
length1: empty set
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
cons: {1}
s: {1}
length: empty set
length1: empty set
Used ordering:
Polynomial interpretation [POLO]:
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(cons(x1, x2)) = 1 + x1 + x2
POL(length(x1)) = x1
POL(length1(x1)) = x1
POL(s(x1)) = x1
length(cons(X, Y)) → s(length1(Y))
length1(X) → length(X)
length: empty set
length1: empty set
length1(X) → length(X)
length: empty set
length1: empty set
Used ordering:
Polynomial interpretation [POLO]:
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(length(x1)) = 0
POL(length1(x1)) = 1 + x1
length1(X) → length(X)