Termination w.r.t. Q of the following Term Rewriting System could be disproven:
Q restricted rewrite system:
The TRS R consists of the following rules:
eq → true
eq → eq
eq → false
inf(X) → cons
take(0, X) → nil
take(s, cons) → cons
length(nil) → 0
length(cons) → s
Q is empty.
↳ QTRS
↳ RRRPoloQTRSProof
Q restricted rewrite system:
The TRS R consists of the following rules:
eq → true
eq → eq
eq → false
inf(X) → cons
take(0, X) → nil
take(s, cons) → cons
length(nil) → 0
length(cons) → s
Q is empty.
The following Q TRS is given: Q restricted rewrite system:
The TRS R consists of the following rules:
eq → true
eq → eq
eq → false
inf(X) → cons
take(0, X) → nil
take(s, cons) → cons
length(nil) → 0
length(cons) → s
Q is empty.
The following rules can be removed by the rule removal processor [15] because they are oriented strictly by a polynomial ordering:
eq → true
eq → false
take(s, cons) → cons
length(nil) → 0
length(cons) → s
Used ordering:
Polynomial interpretation [25]:
POL(0) = 0
POL(cons) = 2
POL(eq) = 2
POL(false) = 0
POL(inf(x1)) = 2 + x1
POL(length(x1)) = 2 + 2·x1
POL(nil) = 0
POL(s) = 1
POL(take(x1, x2)) = 2·x1 + 2·x2
POL(true) = 1
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
Q restricted rewrite system:
The TRS R consists of the following rules:
eq → eq
inf(X) → cons
take(0, X) → nil
Q is empty.
The following Q TRS is given: Q restricted rewrite system:
The TRS R consists of the following rules:
eq → eq
inf(X) → cons
take(0, X) → nil
Q is empty.
The following rules can be removed by the rule removal processor [15] because they are oriented strictly by a polynomial ordering:
inf(X) → cons
take(0, X) → nil
Used ordering:
Polynomial interpretation [25]:
POL(0) = 2
POL(cons) = 1
POL(eq) = 0
POL(inf(x1)) = 2 + x1
POL(nil) = 1
POL(take(x1, x2)) = 2 + 2·x1 + x2
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ AAECC Innermost
Q restricted rewrite system:
The TRS R consists of the following rules:
eq → eq
Q is empty.
We have applied [19,8] to switch to innermost. The TRS R 1 is none
The TRS R 2 is
eq → eq
The signature Sigma is {eq}
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ AAECC Innermost
↳ QTRS
↳ DependencyPairsProof
Q restricted rewrite system:
The TRS R consists of the following rules:
eq → eq
The set Q consists of the following terms:
eq
Using Dependency Pairs [1,15] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:
EQ → EQ
The TRS R consists of the following rules:
eq → eq
The set Q consists of the following terms:
eq
We have to consider all minimal (P,Q,R)-chains.
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ AAECC Innermost
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ UsableRulesProof
Q DP problem:
The TRS P consists of the following rules:
EQ → EQ
The TRS R consists of the following rules:
eq → eq
The set Q consists of the following terms:
eq
We have to consider all minimal (P,Q,R)-chains.
As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [15] we can delete all non-usable rules [17] from R.
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ AAECC Innermost
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ UsableRulesProof
↳ QDP
↳ QReductionProof
Q DP problem:
The TRS P consists of the following rules:
EQ → EQ
R is empty.
The set Q consists of the following terms:
eq
We have to consider all minimal (P,Q,R)-chains.
We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.
eq
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ RRRPoloQTRSProof
↳ QTRS
↳ AAECC Innermost
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ UsableRulesProof
↳ QDP
↳ QReductionProof
↳ QDP
↳ NonTerminationProof
Q DP problem:
The TRS P consists of the following rules:
EQ → EQ
R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We used the non-termination processor [17] to show that the DP problem is infinite.
Found a loop by semiunifying a rule from P directly.
The TRS P consists of the following rules:
EQ → EQ
The TRS R consists of the following rules:none
s = EQ evaluates to t =EQ
Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
- Semiunifier: [ ]
- Matcher: [ ]
Rewriting sequence
The DP semiunifies directly so there is only one rewrite step from EQ to EQ.