YES
0 QTRS
↳1 QTRSRRRProof (⇔, 0 ms)
↳2 QTRS
↳3 RisEmptyProof (⇔, 0 ms)
↳4 YES
f(s(x), y, y) → f(y, x, s(x))
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
POL(f(x1, x2, x3)) = 2·x1 + 2·x2 + x3
POL(s(x1)) = 1 + 2·x1
f(s(x), y, y) → f(y, x, s(x))