We are left with following problem, upon which TcT provides the certificate YES(?,O(n^1)). Strict Trs: { f(x, y) -> g(x, y) , g(h(x), y) -> h(f(x, y)) , g(h(x), y) -> h(g(x, y)) } 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: { f(x, y) -> g(x, y) , g(h(x), y) -> h(f(x, y)) , g(h(x), y) -> h(g(x, y)) } Obligation: innermost runtime complexity Answer: YES(?,O(n^1)) The problem is match-bounded by 2. The enriched problem is compatible with the following automaton. { f_0(3, 3) -> 1 , f_1(3, 3) -> 4 , g_0(3, 3) -> 2 , g_1(3, 3) -> 1 , g_2(3, 3) -> 4 , h_0(3) -> 3 , h_1(1) -> 1 , h_1(1) -> 2 , h_1(1) -> 4 , h_1(4) -> 1 , h_1(4) -> 2 , h_1(4) -> 4 } Hurray, we answered YES(?,O(n^1))