YES Problem: a(a(x1)) -> b(x1) a(b(x1)) -> c(c(x1)) b(c(x1)) -> b(a(a(x1))) Proof: String Reversal Processor: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) DP Processor: DPs: a#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(x1) b#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(b(x1)) c#(b(x1)) -> a#(a(b(x1))) TRS: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) TDG Processor: DPs: a#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(x1) b#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(b(x1)) c#(b(x1)) -> a#(a(b(x1))) TRS: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) graph: c#(b(x1)) -> a#(b(x1)) -> a#(a(x1)) -> b#(x1) c#(b(x1)) -> a#(a(b(x1))) -> a#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(a(b(x1))) b#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(b(x1)) b#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(a(b(x1))) b#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(b(x1)) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> c#(c(x1)) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> c#(x1) Arctic Interpretation Processor: dimension: 4 usable rules: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) interpretation: [b#](x0) = [0 0 -& 0 ]x0 + [0], [0 0 -& 0 ] [-&] [0 0 -& 0 ] [0 ] [b](x0) = [0 0 -& 0 ]x0 + [0 ] [0 0 -& 0 ] [-&], [a#](x0) = [0 0 1 0]x0 + [0], [c#](x0) = [0 1 0 0]x0 + [0], [0 0 0 0 ] [0] [0 0 -& -&] [0] [a](x0) = [0 0 0 0 ]x0 + [0] [0 1 0 0 ] [0], [0 1 0 0 ] [0 ] [-& 0 -& -&] [-&] [c](x0) = [0 1 0 0 ]x0 + [0 ] [-& 1 0 0 ] [0 ] orientation: a#(a(x1)) = [1 1 1 1]x1 + [1] >= [0 0 -& 0 ]x1 + [0] = b#(x1) b#(a(x1)) = [0 1 0 0]x1 + [0] >= [0 1 0 0]x1 + [0] = c#(x1) b#(a(x1)) = [0 1 0 0]x1 + [0] >= [0 1 0 0]x1 + [0] = c#(c(x1)) c#(b(x1)) = [1 1 -& 1 ]x1 + [1] >= [1 1 -& 1 ]x1 + [1] = a#(b(x1)) c#(b(x1)) = [1 1 -& 1 ]x1 + [1] >= [1 1 -& 1 ]x1 + [1] = a#(a(b(x1))) [0 1 0 0] [0] [0 0 -& 0 ] [-&] [0 0 0 0] [0] [0 0 -& 0 ] [0 ] a(a(x1)) = [0 1 0 0]x1 + [0] >= [0 0 -& 0 ]x1 + [0 ] = b(x1) [1 1 0 0] [1] [0 0 -& 0 ] [-&] [0 1 0 0] [0] [0 1 0 0 ] [0 ] [0 1 0 0] [0] [-& 0 -& -&] [-&] b(a(x1)) = [0 1 0 0]x1 + [0] >= [0 1 0 0 ]x1 + [0 ] = c(c(x1)) [0 1 0 0] [0] [0 1 0 0 ] [0 ] [1 1 -& 1 ] [1] [1 1 -& 1 ] [1] [0 0 -& 0 ] [0] [0 0 -& 0 ] [0] c(b(x1)) = [1 1 -& 1 ]x1 + [1] >= [1 1 -& 1 ]x1 + [1] = a(a(b(x1))) [1 1 -& 1 ] [1] [1 1 -& 1 ] [1] problem: DPs: b#(a(x1)) -> c#(x1) b#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(b(x1)) c#(b(x1)) -> a#(a(b(x1))) TRS: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) Restore Modifier: DPs: b#(a(x1)) -> c#(x1) b#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(b(x1)) c#(b(x1)) -> a#(a(b(x1))) TRS: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) EDG Processor: DPs: b#(a(x1)) -> c#(x1) b#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(b(x1)) c#(b(x1)) -> a#(a(b(x1))) TRS: a(a(x1)) -> b(x1) b(a(x1)) -> c(c(x1)) c(b(x1)) -> a(a(b(x1))) graph: b#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(b(x1)) b#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(a(b(x1))) b#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(b(x1)) b#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(a(b(x1))) SCC Processor: #sccs: 0 #rules: 0 #arcs: 4/16