YES
0 QTRS
↳1 FlatCCProof (⇔, 0 ms)
↳2 QTRS
↳3 RootLabelingProof (⇔, 0 ms)
↳4 QTRS
↳5 QTRSRRRProof (⇔, 22 ms)
↳6 QTRS
↳7 RisEmptyProof (⇔, 0 ms)
↳8 YES
f(a) → f(b)
g(b) → g(a)
f(x) → g(x)
f(a) → f(b)
g(b) → g(a)
f(f(x)) → f(g(x))
g(f(x)) → g(g(x))
f_{a}(a) → f_{b}(b)
g_{b}(b) → g_{a}(a)
f_{f_1}(f_{f_1}(x)) → f_{g_1}(g_{f_1}(x))
f_{f_1}(f_{a}(x)) → f_{g_1}(g_{a}(x))
f_{f_1}(f_{b}(x)) → f_{g_1}(g_{b}(x))
f_{f_1}(f_{g_1}(x)) → f_{g_1}(g_{g_1}(x))
g_{f_1}(f_{f_1}(x)) → g_{g_1}(g_{f_1}(x))
g_{f_1}(f_{a}(x)) → g_{g_1}(g_{a}(x))
g_{f_1}(f_{b}(x)) → g_{g_1}(g_{b}(x))
g_{f_1}(f_{g_1}(x)) → g_{g_1}(g_{g_1}(x))
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(a) = 0
POL(b) = 1
POL(f_{a}(x1)) = 2 + x1
POL(f_{b}(x1)) = x1
POL(f_{f_1}(x1)) = 1 + x1
POL(f_{g_1}(x1)) = x1
POL(g_{a}(x1)) = x1
POL(g_{b}(x1)) = x1
POL(g_{f_1}(x1)) = 1 + x1
POL(g_{g_1}(x1)) = x1
f_{a}(a) → f_{b}(b)
g_{b}(b) → g_{a}(a)
f_{f_1}(f_{f_1}(x)) → f_{g_1}(g_{f_1}(x))
f_{f_1}(f_{a}(x)) → f_{g_1}(g_{a}(x))
f_{f_1}(f_{b}(x)) → f_{g_1}(g_{b}(x))
f_{f_1}(f_{g_1}(x)) → f_{g_1}(g_{g_1}(x))
g_{f_1}(f_{f_1}(x)) → g_{g_1}(g_{f_1}(x))
g_{f_1}(f_{a}(x)) → g_{g_1}(g_{a}(x))
g_{f_1}(f_{b}(x)) → g_{g_1}(g_{b}(x))
g_{f_1}(f_{g_1}(x)) → g_{g_1}(g_{g_1}(x))