YES Problem: a(a(x1)) -> b(c(x1)) a(b(x1)) -> c(a(x1)) c(c(x1)) -> a(b(x1)) Proof: String Reversal Processor: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) DP Processor: DPs: a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> c#(x1) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) TDG Processor: DPs: a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> c#(x1) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) graph: c#(c(x1)) -> b#(a(x1)) -> b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> b#(a(x1)) -> b#(a(x1)) -> c#(x1) c#(c(x1)) -> a#(x1) -> a#(a(x1)) -> c#(b(x1)) c#(c(x1)) -> a#(x1) -> a#(a(x1)) -> b#(x1) b#(a(x1)) -> c#(x1) -> c#(c(x1)) -> b#(a(x1)) b#(a(x1)) -> c#(x1) -> c#(c(x1)) -> a#(x1) b#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> b#(a(x1)) a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> a#(x1) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> a#(c(x1)) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> c#(x1) Arctic Interpretation Processor: dimension: 1 usable rules: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) interpretation: [b#](x0) = x0 + 0, [c](x0) = 3x0 + 0, [a#](x0) = x0 + 0, [c#](x0) = x0, [a](x0) = 3x0 + 0, [b](x0) = 3x0 + 0 orientation: a#(a(x1)) = 3x1 + 0 >= x1 + 0 = b#(x1) a#(a(x1)) = 3x1 + 0 >= 3x1 + 0 = c#(b(x1)) b#(a(x1)) = 3x1 + 0 >= x1 = c#(x1) b#(a(x1)) = 3x1 + 0 >= 3x1 + 0 = a#(c(x1)) c#(c(x1)) = 3x1 + 0 >= x1 + 0 = a#(x1) c#(c(x1)) = 3x1 + 0 >= 3x1 + 0 = b#(a(x1)) a(a(x1)) = 6x1 + 3 >= 6x1 + 3 = c(b(x1)) b(a(x1)) = 6x1 + 3 >= 6x1 + 3 = a(c(x1)) c(c(x1)) = 6x1 + 3 >= 6x1 + 3 = b(a(x1)) problem: DPs: a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) Restore Modifier: DPs: a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) EDG Processor: DPs: a#(a(x1)) -> b#(x1) a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) graph: c#(c(x1)) -> b#(a(x1)) -> b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(x1) -> a#(a(x1)) -> b#(x1) c#(c(x1)) -> a#(x1) -> a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> b#(x1) b#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> c#(b(x1)) a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> a#(x1) a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> b#(a(x1)) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> a#(c(x1)) Arctic Interpretation Processor: dimension: 1 usable rules: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) interpretation: [b#](x0) = x0, [c](x0) = 1x0, [a#](x0) = x0, [c#](x0) = x0, [a](x0) = 1x0, [b](x0) = 1x0 orientation: a#(a(x1)) = 1x1 >= x1 = b#(x1) a#(a(x1)) = 1x1 >= 1x1 = c#(b(x1)) b#(a(x1)) = 1x1 >= 1x1 = a#(c(x1)) c#(c(x1)) = 1x1 >= x1 = a#(x1) c#(c(x1)) = 1x1 >= 1x1 = b#(a(x1)) a(a(x1)) = 2x1 >= 2x1 = c(b(x1)) b(a(x1)) = 2x1 >= 2x1 = a(c(x1)) c(c(x1)) = 2x1 >= 2x1 = b(a(x1)) problem: DPs: a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) Restore Modifier: DPs: a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) EDG Processor: DPs: a#(a(x1)) -> c#(b(x1)) b#(a(x1)) -> a#(c(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) graph: c#(c(x1)) -> b#(a(x1)) -> b#(a(x1)) -> a#(c(x1)) b#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> c#(b(x1)) a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> b#(a(x1)) Arctic Interpretation Processor: dimension: 3 usable rules: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) interpretation: [b#](x0) = [0 1 1]x0 + [1], [1 0 1 ] [0 ] [c](x0) = [1 0 0 ]x0 + [0 ] [0 -& 0 ] [-&], [a#](x0) = [0 0 1]x0 + [0], [c#](x0) = [1 0 0]x0, [0 0 1] [0 ] [a](x0) = [1 0 0]x0 + [-&] [0 0 1] [-&], [0 0 1] [b](x0) = [1 1 0]x0 [0 0 0] orientation: a#(a(x1)) = [1 1 2]x1 + [0] >= [1 1 2]x1 = c#(b(x1)) b#(a(x1)) = [2 1 2]x1 + [1] >= [1 0 1]x1 + [0] = a#(c(x1)) c#(c(x1)) = [2 1 2]x1 + [1] >= [2 1 2]x1 + [1] = b#(a(x1)) [1 1 2] [0] [1 1 2] [0 ] a(a(x1)) = [1 1 2]x1 + [1] >= [1 1 2]x1 + [0 ] = c(b(x1)) [1 1 2] [0] [0 0 1] [-&] [1 1 2] [0] [1 0 1] [0] b(a(x1)) = [2 1 2]x1 + [1] >= [2 1 2]x1 + [1] = a(c(x1)) [1 0 1] [0] [1 0 1] [0] [2 1 2] [1] [1 1 2] [0] c(c(x1)) = [2 1 2]x1 + [1] >= [2 1 2]x1 + [1] = b(a(x1)) [1 0 1] [0] [1 0 1] [0] problem: DPs: a#(a(x1)) -> c#(b(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) Restore Modifier: DPs: a#(a(x1)) -> c#(b(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) EDG Processor: DPs: a#(a(x1)) -> c#(b(x1)) c#(c(x1)) -> b#(a(x1)) TRS: a(a(x1)) -> c(b(x1)) b(a(x1)) -> a(c(x1)) c(c(x1)) -> b(a(x1)) graph: a#(a(x1)) -> c#(b(x1)) -> c#(c(x1)) -> b#(a(x1)) SCC Processor: #sccs: 0 #rules: 0 #arcs: 1/4