TRS:
 {f(x, c(x), c(y)) -> f(y, y, f(y, x, y)),
     f(s(x), y, z) -> f(x, s(c(y)), c(z)),
     f(c(x), x, y) -> c(y),
           g(x, y) -> x,
           g(x, y) -> y}
 Fail