YES
0 QTRS
↳1 QTRSRRRProof (⇔, 0 ms)
↳2 QTRS
↳3 RisEmptyProof (⇔, 0 ms)
↳4 YES
f(X) → cons(X, n__f(n__g(X)))
g(0) → s(0)
g(s(X)) → s(s(g(X)))
sel(0, cons(X, Y)) → X
sel(s(X), cons(Y, Z)) → sel(X, activate(Z))
f(X) → n__f(X)
g(X) → n__g(X)
activate(n__f(X)) → f(activate(X))
activate(n__g(X)) → g(activate(X))
activate(X) → X
sel2 > activate1 > f1 > nf1 > cons2
sel2 > activate1 > f1 > ng1 > cons2
sel2 > activate1 > g1 > ng1 > cons2
sel2 > activate1 > g1 > 0 > cons2
sel2 > activate1 > g1 > s1 > cons2
f1: [1]
cons2: [2,1]
nf1: multiset
ng1: multiset
g1: multiset
0: multiset
s1: multiset
sel2: [1,2]
activate1: [1]
f(X) → cons(X, n__f(n__g(X)))
g(0) → s(0)
g(s(X)) → s(s(g(X)))
sel(0, cons(X, Y)) → X
sel(s(X), cons(Y, Z)) → sel(X, activate(Z))
f(X) → n__f(X)
g(X) → n__g(X)
activate(n__f(X)) → f(activate(X))
activate(n__g(X)) → g(activate(X))
activate(X) → X