We are left with following problem, upon which TcT provides the certificate YES(?,O(n^1)). Strict Trs: { g(x, h(y, z)) -> h(g(x, y), z) , g(f(x, y), z) -> f(x, g(y, z)) , g(h(x, y), z) -> g(x, f(y, z)) } Obligation: runtime complexity Answer: YES(?,O(n^1)) The input is overlay and right-linear. Switching to innermost rewriting. We are left with following problem, upon which TcT provides the certificate YES(?,O(n^1)). Strict Trs: { g(x, h(y, z)) -> h(g(x, y), z) , g(f(x, y), z) -> f(x, g(y, z)) , g(h(x, y), z) -> g(x, f(y, z)) } Obligation: innermost runtime complexity Answer: YES(?,O(n^1)) The problem is match-bounded by 1. The enriched problem is compatible with the following automaton. { g_0(2, 2) -> 1 , g_1(2, 2) -> 3 , g_1(2, 4) -> 1 , g_1(2, 4) -> 3 , f_0(2, 2) -> 2 , f_1(2, 2) -> 4 , f_1(2, 3) -> 1 , f_1(2, 3) -> 3 , f_1(2, 4) -> 4 , h_0(2, 2) -> 2 , h_1(3, 2) -> 1 , h_1(3, 2) -> 3 } Hurray, we answered YES(?,O(n^1))