YES Problem: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 Proof: DP Processor: DPs: a#(x1) -> c#(x1) c#(a(b(x1))) -> c#(x1) c#(a(b(x1))) -> a#(c(x1)) c#(a(b(x1))) -> a#(a(c(x1))) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 TDG Processor: DPs: a#(x1) -> c#(x1) c#(a(b(x1))) -> c#(x1) c#(a(b(x1))) -> a#(c(x1)) c#(a(b(x1))) -> a#(a(c(x1))) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 graph: c#(a(b(x1))) -> c#(x1) -> c#(a(b(x1))) -> a#(a(c(x1))) c#(a(b(x1))) -> c#(x1) -> c#(a(b(x1))) -> a#(c(x1)) c#(a(b(x1))) -> c#(x1) -> c#(a(b(x1))) -> c#(x1) c#(a(b(x1))) -> a#(c(x1)) -> a#(x1) -> c#(x1) c#(a(b(x1))) -> a#(a(c(x1))) -> a#(x1) -> c#(x1) a#(x1) -> c#(x1) -> c#(a(b(x1))) -> a#(a(c(x1))) a#(x1) -> c#(x1) -> c#(a(b(x1))) -> a#(c(x1)) a#(x1) -> c#(x1) -> c#(a(b(x1))) -> c#(x1) Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 interpretation: [c#](x0) = [0 0]x0 + [0], [a#](x0) = [0 0]x0 + [0], [0 0] [0] [b](x0) = [0 0]x0 + [0], [0 0] [0 ] [c](x0) = [0 0]x0 + [-&], [0 0] [0] [a](x0) = [2 0]x0 + [0] orientation: a#(x1) = [0 0]x1 + [0] >= [0 0]x1 + [0] = c#(x1) c#(a(b(x1))) = [2 2]x1 + [2] >= [0 0]x1 + [0] = c#(x1) c#(a(b(x1))) = [2 2]x1 + [2] >= [0 0]x1 + [0] = a#(c(x1)) c#(a(b(x1))) = [2 2]x1 + [2] >= [2 2]x1 + [2] = a#(a(c(x1))) [0 0] [0] [0 0] [0] a(x1) = [2 0]x1 + [0] >= [0 0]x1 + [0] = b(b(c(x1))) [2 2] [2] [2 2] [2] c(a(b(x1))) = [2 2]x1 + [2] >= [2 2]x1 + [2] = a(a(c(x1))) [0 0] [0] c(b(x1)) = [0 0]x1 + [0] >= x1 = x1 problem: DPs: a#(x1) -> c#(x1) c#(a(b(x1))) -> a#(a(c(x1))) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 Restore Modifier: DPs: a#(x1) -> c#(x1) c#(a(b(x1))) -> a#(a(c(x1))) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 EDG Processor: DPs: a#(x1) -> c#(x1) c#(a(b(x1))) -> a#(a(c(x1))) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 graph: c#(a(b(x1))) -> a#(a(c(x1))) -> a#(x1) -> c#(x1) a#(x1) -> c#(x1) -> c#(a(b(x1))) -> a#(a(c(x1))) Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 interpretation: [c#](x0) = [0 0]x0, [a#](x0) = [0 0]x0, [0 0] [b](x0) = [1 0]x0, [0 -&] [c](x0) = [0 -&]x0, [1 1] [a](x0) = [1 0]x0 orientation: a#(x1) = [0 0]x1 >= [0 0]x1 = c#(x1) c#(a(b(x1))) = [2 1]x1 >= [1 -&]x1 = a#(a(c(x1))) [1 1] [1 -&] a(x1) = [1 0]x1 >= [1 -&]x1 = b(b(c(x1))) [2 1] [2 -&] c(a(b(x1))) = [2 1]x1 >= [2 -&]x1 = a(a(c(x1))) [0 0] c(b(x1)) = [0 0]x1 >= x1 = x1 problem: DPs: a#(x1) -> c#(x1) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 Restore Modifier: DPs: a#(x1) -> c#(x1) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 EDG Processor: DPs: a#(x1) -> c#(x1) TRS: a(x1) -> b(b(c(x1))) c(a(b(x1))) -> a(a(c(x1))) c(b(x1)) -> x1 graph: Qed