YES Problem: a(x1) -> x1 a(b(x1)) -> b(a(c(x1))) b(x1) -> x1 c(c(x1)) -> c(b(a(x1))) Proof: String Reversal Processor: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) DP Processor: DPs: b#(a(x1)) -> b#(x1) b#(a(x1)) -> a#(b(x1)) b#(a(x1)) -> c#(a(b(x1))) c#(c(x1)) -> b#(c(x1)) c#(c(x1)) -> a#(b(c(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) TDG Processor: DPs: b#(a(x1)) -> b#(x1) b#(a(x1)) -> a#(b(x1)) b#(a(x1)) -> c#(a(b(x1))) c#(c(x1)) -> b#(c(x1)) c#(c(x1)) -> a#(b(c(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) graph: c#(c(x1)) -> b#(c(x1)) -> b#(a(x1)) -> c#(a(b(x1))) c#(c(x1)) -> b#(c(x1)) -> b#(a(x1)) -> a#(b(x1)) c#(c(x1)) -> b#(c(x1)) -> b#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(a(b(x1))) -> c#(c(x1)) -> a#(b(c(x1))) b#(a(x1)) -> c#(a(b(x1))) -> c#(c(x1)) -> b#(c(x1)) b#(a(x1)) -> b#(x1) -> b#(a(x1)) -> c#(a(b(x1))) b#(a(x1)) -> b#(x1) -> b#(a(x1)) -> a#(b(x1)) b#(a(x1)) -> b#(x1) -> b#(a(x1)) -> b#(x1) SCC Processor: #sccs: 1 #rules: 3 #arcs: 8/25 DPs: c#(c(x1)) -> b#(c(x1)) b#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(a(b(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) interpretation: [b#](x0) = [-& 0 ]x0 + [0], [0 0] [b](x0) = [0 0]x0, [c#](x0) = [1 -&]x0, [0 0] [-&] [a](x0) = [1 1]x0 + [0 ], [1 0] [0] [c](x0) = [1 0]x0 + [0] orientation: c#(c(x1)) = [2 1]x1 + [1] >= [1 0]x1 + [0] = b#(c(x1)) b#(a(x1)) = [1 1]x1 + [0] >= [-& 0 ]x1 + [0] = b#(x1) b#(a(x1)) = [1 1]x1 + [0] >= [1 1]x1 = c#(a(b(x1))) [0 0] [-&] a(x1) = [1 1]x1 + [0 ] >= x1 = x1 [1 1] [0] [1 1] [0] b(a(x1)) = [1 1]x1 + [0] >= [1 1]x1 + [0] = c(a(b(x1))) [0 0] b(x1) = [0 0]x1 >= x1 = x1 [2 1] [1] [1 0] [0] c(c(x1)) = [2 1]x1 + [1] >= [2 1]x1 + [1] = a(b(c(x1))) problem: DPs: b#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(a(b(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) Restore Modifier: DPs: b#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(a(b(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) EDG Processor: DPs: b#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(a(b(x1))) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) graph: b#(a(x1)) -> b#(x1) -> b#(a(x1)) -> b#(x1) b#(a(x1)) -> b#(x1) -> b#(a(x1)) -> c#(a(b(x1))) SCC Processor: #sccs: 1 #rules: 1 #arcs: 2/4 DPs: b#(a(x1)) -> b#(x1) TRS: a(x1) -> x1 b(a(x1)) -> c(a(b(x1))) b(x1) -> x1 c(c(x1)) -> a(b(c(x1))) Usable Rule Processor: DPs: b#(a(x1)) -> b#(x1) TRS: Arctic Interpretation Processor: dimension: 4 usable rules: interpretation: [b#](x0) = [0 -& -& -&]x0, [1 0 0 0] [0] [0 0 0 0] [0] [a](x0) = [1 0 0 0]x0 + [0] [0 0 0 0] [0] orientation: b#(a(x1)) = [1 0 0 0]x1 + [0] >= [0 -& -& -&]x1 = b#(x1) problem: DPs: TRS: Qed