MAYBE MAYBE TRS: { +(x, +(y, z)) -> +(+(x, y), z), +(x, 0()) -> x, +(x, s(y)) -> s(+(x, y)), +(0(), y) -> y, +(s(x), y) -> s(+(x, y)), f(h(x, h(y, z))) -> f(h(+(x, y), z)), f(g(f(x))) -> f(h(s(0()), x)), f(g(h(x, y))) -> f(h(s(x), y)) } DUP: We consider a non-duplicating system. Trs: { +(x, +(y, z)) -> +(+(x, y), z), +(x, 0()) -> x, +(x, s(y)) -> s(+(x, y)), +(0(), y) -> y, +(s(x), y) -> s(+(x, y)), f(h(x, h(y, z))) -> f(h(+(x, y), z)), f(g(f(x))) -> f(h(s(0()), x)), f(g(h(x, y))) -> f(h(s(x), y)) } Fail