YES Problem: cond(true(),x) -> cond(odd(x),p(p(p(x)))) odd(0()) -> false() odd(s(0())) -> true() odd(s(s(x))) -> odd(x) p(0()) -> 0() p(s(x)) -> x Proof: DP Processor: DPs: cond#(true(),x) -> p#(x) cond#(true(),x) -> p#(p(x)) cond#(true(),x) -> p#(p(p(x))) cond#(true(),x) -> odd#(x) cond#(true(),x) -> cond#(odd(x),p(p(p(x)))) odd#(s(s(x))) -> odd#(x) TRS: cond(true(),x) -> cond(odd(x),p(p(p(x)))) odd(0()) -> false() odd(s(0())) -> true() odd(s(s(x))) -> odd(x) p(0()) -> 0() p(s(x)) -> x Usable Rule Processor: DPs: cond#(true(),x) -> p#(x) cond#(true(),x) -> p#(p(x)) cond#(true(),x) -> p#(p(p(x))) cond#(true(),x) -> odd#(x) cond#(true(),x) -> cond#(odd(x),p(p(p(x)))) odd#(s(s(x))) -> odd#(x) TRS: p(0()) -> 0() p(s(x)) -> x odd(0()) -> false() odd(s(0())) -> true() odd(s(s(x))) -> odd(x) Arctic Interpretation Processor: dimension: 1 usable rules: p(0()) -> 0() p(s(x)) -> x odd(0()) -> false() odd(s(0())) -> true() odd(s(s(x))) -> odd(x) interpretation: [odd#](x0) = 1x0 + 0, [p#](x0) = 2, [cond#](x0, x1) = x0 + 2x1 + 0, [s](x0) = 2x0 + 4, [false] = 0, [0] = 0, [p](x0) = -1x0 + 1, [odd](x0) = 1x0 + 0, [true] = 4 orientation: cond#(true(),x) = 2x + 4 >= 2 = p#(x) cond#(true(),x) = 2x + 4 >= 2 = p#(p(x)) cond#(true(),x) = 2x + 4 >= 2 = p#(p(p(x))) cond#(true(),x) = 2x + 4 >= 1x + 0 = odd#(x) cond#(true(),x) = 2x + 4 >= 1x + 3 = cond#(odd(x),p(p(p(x)))) odd#(s(s(x))) = 5x + 7 >= 1x + 0 = odd#(x) p(0()) = 1 >= 0 = 0() p(s(x)) = 1x + 3 >= x = x odd(0()) = 1 >= 0 = false() odd(s(0())) = 5 >= 4 = true() odd(s(s(x))) = 5x + 7 >= 1x + 0 = odd(x) problem: DPs: TRS: p(0()) -> 0() p(s(x)) -> x odd(0()) -> false() odd(s(0())) -> true() odd(s(s(x))) -> odd(x) Qed