YES Problem: a(x1) -> x1 a(b(x1)) -> a(c(b(b(c(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) Proof: String Reversal Processor: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) DP Processor: DPs: b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> c#(b(b(c(a(x1))))) c#(c(x1)) -> a#(x1) TRS: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) TDG Processor: DPs: b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> c#(b(b(c(a(x1))))) c#(c(x1)) -> a#(x1) TRS: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) graph: b#(a(x1)) -> c#(b(b(c(a(x1))))) -> c#(c(x1)) -> a#(x1) b#(a(x1)) -> c#(a(x1)) -> c#(c(x1)) -> a#(x1) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> c#(b(b(c(a(x1))))) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> c#(b(b(c(a(x1))))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> c#(a(x1)) CDG Processor: DPs: b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> c#(b(b(c(a(x1))))) c#(c(x1)) -> a#(x1) TRS: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) graph: b#(a(x1)) -> c#(b(b(c(a(x1))))) -> c#(c(x1)) -> a#(x1) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> b#(c(a(x1))) -> b#(a(x1)) -> c#(b(b(c(a(x1))))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> c#(a(x1)) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> b#(b(c(a(x1)))) b#(a(x1)) -> b#(b(c(a(x1)))) -> b#(a(x1)) -> c#(b(b(c(a(x1))))) SCC Processor: #sccs: 1 #rules: 2 #arcs: 9/25 DPs: b#(a(x1)) -> b#(c(a(x1))) b#(a(x1)) -> b#(b(c(a(x1)))) TRS: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) Arctic Interpretation Processor: dimension: 2 interpretation: [b#](x0) = [-& 0 ]x0 + [0], [1 0 ] [1] [c](x0) = [0 -&]x0 + [0], [0 1 ] [0] [b](x0) = [-& 0 ]x0 + [0], [0 -&] [-&] [a](x0) = [1 0 ]x0 + [1 ] orientation: b#(a(x1)) = [1 0]x1 + [1] >= [0 -&]x1 + [0] = b#(c(a(x1))) b#(a(x1)) = [1 0]x1 + [1] >= [0 -&]x1 + [0] = b#(b(c(a(x1)))) [0 -&] [-&] a(x1) = [1 0 ]x1 + [1 ] >= x1 = x1 [2 1] [2] [2 1] [2] b(a(x1)) = [1 0]x1 + [1] >= [1 0]x1 + [1] = c(b(b(c(a(x1))))) [0 1 ] [0] b(x1) = [-& 0 ]x1 + [0] >= x1 = x1 [2 1] [2] [0 -&] [-&] c(c(x1)) = [1 0]x1 + [1] >= [1 0 ]x1 + [1 ] = a(x1) problem: DPs: TRS: a(x1) -> x1 b(a(x1)) -> c(b(b(c(a(x1))))) b(x1) -> x1 c(c(x1)) -> a(x1) Qed