YES(?,O(n^2)) We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict Trs: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) , -(x, 0()) -> x , -(0(), y) -> 0() , -(s(x), s(y)) -> -(x, y) } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) We add following dependency tuples: Strict DPs: { exp^#(x, 0()) -> c_1() , exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , *^#(0(), y) -> c_3() , *^#(s(x), y) -> c_4(*^#(x, y)) , -^#(x, 0()) -> c_5() , -^#(0(), y) -> c_6() , -^#(s(x), s(y)) -> c_7(-^#(x, y)) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { exp^#(x, 0()) -> c_1() , exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , *^#(0(), y) -> c_3() , *^#(s(x), y) -> c_4(*^#(x, y)) , -^#(x, 0()) -> c_5() , -^#(0(), y) -> c_6() , -^#(s(x), s(y)) -> c_7(-^#(x, y)) } Weak Trs: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) , -(x, 0()) -> x , -(0(), y) -> 0() , -(s(x), s(y)) -> -(x, y) } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) We estimate the number of application of {1,3,5,6} by applications of Pre({1,3,5,6}) = {2,4,7}. Here rules are labeled as follows: DPs: { 1: exp^#(x, 0()) -> c_1() , 2: exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , 3: *^#(0(), y) -> c_3() , 4: *^#(s(x), y) -> c_4(*^#(x, y)) , 5: -^#(x, 0()) -> c_5() , 6: -^#(0(), y) -> c_6() , 7: -^#(s(x), s(y)) -> c_7(-^#(x, y)) } We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , *^#(s(x), y) -> c_4(*^#(x, y)) , -^#(s(x), s(y)) -> c_7(-^#(x, y)) } Weak DPs: { exp^#(x, 0()) -> c_1() , *^#(0(), y) -> c_3() , -^#(x, 0()) -> c_5() , -^#(0(), y) -> c_6() } Weak Trs: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) , -(x, 0()) -> x , -(0(), y) -> 0() , -(s(x), s(y)) -> -(x, y) } 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. { exp^#(x, 0()) -> c_1() , *^#(0(), y) -> c_3() , -^#(x, 0()) -> c_5() , -^#(0(), y) -> c_6() } We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , *^#(s(x), y) -> c_4(*^#(x, y)) , -^#(s(x), s(y)) -> c_7(-^#(x, y)) } Weak Trs: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) , -(x, 0()) -> x , -(0(), y) -> 0() , -(s(x), s(y)) -> -(x, y) } Obligation: innermost runtime complexity Answer: YES(?,O(n^2)) We replace rewrite rules by usable rules: Weak Usable Rules: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) } We are left with following problem, upon which TcT provides the certificate YES(?,O(n^2)). Strict DPs: { exp^#(x, s(y)) -> c_2(*^#(x, exp(x, y)), exp^#(x, y)) , *^#(s(x), y) -> c_4(*^#(x, y)) , -^#(s(x), s(y)) -> c_7(-^#(x, y)) } Weak Trs: { exp(x, 0()) -> s(0()) , exp(x, s(y)) -> *(x, exp(x, y)) , *(0(), y) -> 0() , *(s(x), y) -> +(y, *(x, y)) } 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(exp) = {}, safe(0) = {}, safe(s) = {1}, safe(*) = {}, safe(+) = {1, 2}, safe(exp^#) = {}, safe(c_2) = {}, safe(*^#) = {2}, safe(c_4) = {}, safe(-^#) = {}, safe(c_7) = {} and precedence exp > *, exp > *^#, exp^# > *, exp^# > *^#, -^# > *, -^# > *^#, exp ~ exp^#, exp ~ -^#, * ~ *^#, exp^# ~ -^# . Following symbols are considered recursive: {exp, *, exp^#, *^#, -^#} The recursion depth is 2. Further, following argument filtering is employed: pi(exp) = [], pi(0) = [], pi(s) = [1], pi(*) = [2], pi(+) = [], pi(exp^#) = [1, 2], pi(c_2) = [1, 2], pi(*^#) = [1], pi(c_4) = [1], pi(-^#) = [1, 2], pi(c_7) = [1] Usable defined function symbols are a subset of: {exp^#, *^#, -^#} For your convenience, here are the satisfied ordering constraints: pi(exp^#(x, s(y))) = exp^#(x, s(; y);) > c_2(*^#(x;), exp^#(x, y;);) = pi(c_2(*^#(x, exp(x, y)), exp^#(x, y))) pi(*^#(s(x), y)) = *^#(s(; x);) > c_4(*^#(x;);) = pi(c_4(*^#(x, y))) pi(-^#(s(x), s(y))) = -^#(s(; x), s(; y);) > c_7(-^#(x, y;);) = pi(c_7(-^#(x, y))) Hurray, we answered YES(?,O(n^2))