MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { diff(x, y) -> cond1(equal(x, y), x, y) , cond1(true(), x, y) -> 0() , cond1(false(), x, y) -> cond2(gt(x, y), x, y) , equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , cond2(true(), x, y) -> s(diff(x, s(y))) , cond2(false(), x, y) -> s(diff(s(x), y)) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } Obligation: innermost runtime complexity Answer: MAYBE We add following dependency tuples: Strict DPs: { diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , cond1^#(true(), x, y) -> c_2() , cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , equal^#(0(), 0()) -> c_4() , equal^#(0(), s(y)) -> c_5() , equal^#(s(x), 0()) -> c_6() , equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , gt^#(0(), v) -> c_10() , gt^#(s(u), 0()) -> c_11() , gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , cond1^#(true(), x, y) -> c_2() , cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , equal^#(0(), 0()) -> c_4() , equal^#(0(), s(y)) -> c_5() , equal^#(s(x), 0()) -> c_6() , equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , gt^#(0(), v) -> c_10() , gt^#(s(u), 0()) -> c_11() , gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } Weak Trs: { diff(x, y) -> cond1(equal(x, y), x, y) , cond1(true(), x, y) -> 0() , cond1(false(), x, y) -> cond2(gt(x, y), x, y) , equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , cond2(true(), x, y) -> s(diff(x, s(y))) , cond2(false(), x, y) -> s(diff(s(x), y)) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } Obligation: innermost runtime complexity Answer: MAYBE We estimate the number of application of {2,4,5,6,10,11} by applications of Pre({2,4,5,6,10,11}) = {1,3,7,12}. Here rules are labeled as follows: DPs: { 1: diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , 2: cond1^#(true(), x, y) -> c_2() , 3: cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , 4: equal^#(0(), 0()) -> c_4() , 5: equal^#(0(), s(y)) -> c_5() , 6: equal^#(s(x), 0()) -> c_6() , 7: equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , 8: cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , 9: cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , 10: gt^#(0(), v) -> c_10() , 11: gt^#(s(u), 0()) -> c_11() , 12: gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } Weak DPs: { cond1^#(true(), x, y) -> c_2() , equal^#(0(), 0()) -> c_4() , equal^#(0(), s(y)) -> c_5() , equal^#(s(x), 0()) -> c_6() , gt^#(0(), v) -> c_10() , gt^#(s(u), 0()) -> c_11() } Weak Trs: { diff(x, y) -> cond1(equal(x, y), x, y) , cond1(true(), x, y) -> 0() , cond1(false(), x, y) -> cond2(gt(x, y), x, y) , equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , cond2(true(), x, y) -> s(diff(x, s(y))) , cond2(false(), x, y) -> s(diff(s(x), y)) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } Obligation: innermost runtime complexity Answer: MAYBE The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. { cond1^#(true(), x, y) -> c_2() , equal^#(0(), 0()) -> c_4() , equal^#(0(), s(y)) -> c_5() , equal^#(s(x), 0()) -> c_6() , gt^#(0(), v) -> c_10() , gt^#(s(u), 0()) -> c_11() } We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } Weak Trs: { diff(x, y) -> cond1(equal(x, y), x, y) , cond1(true(), x, y) -> 0() , cond1(false(), x, y) -> cond2(gt(x, y), x, y) , equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , cond2(true(), x, y) -> s(diff(x, s(y))) , cond2(false(), x, y) -> s(diff(s(x), y)) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } Obligation: innermost runtime complexity Answer: MAYBE We replace rewrite rules by usable rules: Weak Usable Rules: { equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { diff^#(x, y) -> c_1(cond1^#(equal(x, y), x, y), equal^#(x, y)) , cond1^#(false(), x, y) -> c_3(cond2^#(gt(x, y), x, y), gt^#(x, y)) , equal^#(s(x), s(y)) -> c_7(equal^#(x, y)) , cond2^#(true(), x, y) -> c_8(diff^#(x, s(y))) , cond2^#(false(), x, y) -> c_9(diff^#(s(x), y)) , gt^#(s(u), s(v)) -> c_12(gt^#(u, v)) } Weak Trs: { equal(0(), 0()) -> true() , equal(0(), s(y)) -> false() , equal(s(x), 0()) -> false() , equal(s(x), s(y)) -> equal(x, y) , gt(0(), v) -> false() , gt(s(u), 0()) -> true() , gt(s(u), s(v)) -> gt(u, v) } Obligation: innermost runtime complexity Answer: MAYBE The input cannot be shown compatible Arrrr..