TRS: { a__h(X) -> a__g(mark(X), X), a__g(a(), X) -> a__f(b(), X), a__f(X, X) -> a__h(a__a()), a__a() -> b(), mark(h(X)) -> a__h(mark(X)), mark(g(X1, X2)) -> a__g(mark(X1), X2), mark(a()) -> a__a(), mark(f(X1, X2)) -> a__f(mark(X1), X2), mark(b()) -> b(), a__h(X) -> h(X), a__g(X1, X2) -> g(X1, X2), a__a() -> a(), a__f(X1, X2) -> f(X1, X2)} Fail