YES(O(1),O(n^2)) We are left with following problem, upon which TcT provides the certificate YES(O(1),O(n^2)). Strict Trs: { sum(0()) -> 0() , sum(s(x)) -> +(sum(x), s(x)) , sum1(0()) -> 0() , sum1(s(x)) -> s(+(sum1(x), +(x, x))) } Obligation: innermost runtime complexity Answer: YES(O(1),O(n^2)) We add following weak dependency pairs: Strict DPs: { sum^#(0()) -> c_1() , sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(0()) -> c_3() , sum1^#(s(x)) -> c_4(sum1^#(x)) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate YES(O(1),O(n^2)). Strict DPs: { sum^#(0()) -> c_1() , sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(0()) -> c_3() , sum1^#(s(x)) -> c_4(sum1^#(x)) } Strict Trs: { sum(0()) -> 0() , sum(s(x)) -> +(sum(x), s(x)) , sum1(0()) -> 0() , sum1(s(x)) -> s(+(sum1(x), +(x, x))) } Obligation: innermost runtime complexity Answer: YES(O(1),O(n^2)) No rule is usable, rules are removed from the input problem. We are left with following problem, upon which TcT provides the certificate YES(O(1),O(n^2)). Strict DPs: { sum^#(0()) -> c_1() , sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(0()) -> c_3() , sum1^#(s(x)) -> c_4(sum1^#(x)) } Obligation: innermost runtime complexity Answer: YES(O(1),O(n^2)) The weightgap principle applies (using the following constant growth matrix-interpretation) The following argument positions are usable: Uargs(c_2) = {1}, Uargs(c_4) = {1} TcT has computed following constructor-restricted matrix interpretation. [0] = [0] [s](x1) = [1] x1 + [0] [sum^#](x1) = [1] [c_1] = [0] [c_2](x1) = [1] x1 + [1] [sum1^#](x1) = [0] [c_3] = [1] [c_4](x1) = [1] x1 + [2] This order satisfies following ordering constraints: Further, it can be verified that all rules not oriented are covered by the weightgap condition. We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(0()) -> c_3() , sum1^#(s(x)) -> c_4(sum1^#(x)) } Weak DPs: { sum^#(0()) -> c_1() } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) We estimate the number of application of {2} by applications of Pre({2}) = {3}. Here rules are labeled as follows: DPs: { 1: sum^#(s(x)) -> c_2(sum^#(x)) , 2: sum1^#(0()) -> c_3() , 3: sum1^#(s(x)) -> c_4(sum1^#(x)) , 4: sum^#(0()) -> c_1() } We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(s(x)) -> c_4(sum1^#(x)) } Weak DPs: { sum^#(0()) -> c_1() , sum1^#(0()) -> c_3() } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. { sum^#(0()) -> c_1() , sum1^#(0()) -> c_3() } We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { sum^#(s(x)) -> c_2(sum^#(x)) , sum1^#(s(x)) -> c_4(sum1^#(x)) } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) The input was oriented with the instance of 'Small Polynomial Path Order (PS)' as induced by the safe mapping safe(s) = {1}, safe(sum^#) = {}, safe(c_2) = {}, safe(sum1^#) = {}, safe(c_4) = {} and precedence sum1^# > sum^# . Following symbols are considered recursive: {sum^#, sum1^#} The recursion depth is 2. Further, following argument filtering is employed: pi(s) = [1], pi(sum^#) = [1], pi(c_2) = [1], pi(sum1^#) = [1], pi(c_4) = [1] Usable defined function symbols are a subset of: {sum^#, sum1^#} For your convenience, here are the satisfied ordering constraints: pi(sum^#(s(x))) = sum^#(s(; x);) > c_2(sum^#(x;);) = pi(c_2(sum^#(x))) pi(sum1^#(s(x))) = sum1^#(s(; x);) > c_4(sum1^#(x;);) = pi(c_4(sum1^#(x))) Hurray, we answered YES(O(1),O(n^2))