YES Problem: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) conv(0()) -> cons(nil(),0()) conv(s(x)) -> cons(conv(half(s(x))),lastbit(s(x))) Proof: DP Processor: DPs: half#(s(s(x))) -> half#(x) lastbit#(s(s(x))) -> lastbit#(x) conv#(s(x)) -> lastbit#(s(x)) conv#(s(x)) -> half#(s(x)) conv#(s(x)) -> conv#(half(s(x))) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) conv(0()) -> cons(nil(),0()) conv(s(x)) -> cons(conv(half(s(x))),lastbit(s(x))) Usable Rule Processor: DPs: half#(s(s(x))) -> half#(x) lastbit#(s(s(x))) -> lastbit#(x) conv#(s(x)) -> lastbit#(s(x)) conv#(s(x)) -> half#(s(x)) conv#(s(x)) -> conv#(half(s(x))) TRS: half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) half(0()) -> 0() Arctic Interpretation Processor: dimension: 1 usable rules: half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) half(0()) -> 0() interpretation: [conv#](x0) = 1x0 + -16, [lastbit#](x0) = x0 + -16, [half#](x0) = x0, [s](x0) = 2x0 + 5, [half](x0) = -1x0 + 3, [0] = 0 orientation: half#(s(s(x))) = 4x + 7 >= x = half#(x) lastbit#(s(s(x))) = 4x + 7 >= x + -16 = lastbit#(x) conv#(s(x)) = 3x + 6 >= 2x + 5 = lastbit#(s(x)) conv#(s(x)) = 3x + 6 >= 2x + 5 = half#(s(x)) conv#(s(x)) = 3x + 6 >= 2x + 5 = conv#(half(s(x))) half(s(0())) = 4 >= 0 = 0() half(s(s(x))) = 3x + 6 >= 1x + 5 = s(half(x)) half(0()) = 3 >= 0 = 0() problem: DPs: TRS: half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) half(0()) -> 0() Qed