YES Problem: a(x1) -> b(b(c(b(c(x1))))) c(b(b(x1))) -> a(x1) c(c(x1)) -> x1 Proof: String Reversal Processor: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 DP Processor: DPs: a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> c#(b(b(x1))) a#(x1) -> b#(c(b(b(x1)))) a#(x1) -> c#(b(c(b(b(x1))))) b#(b(c(x1))) -> a#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 TDG Processor: DPs: a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> c#(b(b(x1))) a#(x1) -> b#(c(b(b(x1)))) a#(x1) -> c#(b(c(b(b(x1))))) b#(b(c(x1))) -> a#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 graph: b#(b(c(x1))) -> a#(x1) -> a#(x1) -> c#(b(c(b(b(x1))))) b#(b(c(x1))) -> a#(x1) -> a#(x1) -> b#(c(b(b(x1)))) b#(b(c(x1))) -> a#(x1) -> a#(x1) -> c#(b(b(x1))) b#(b(c(x1))) -> a#(x1) -> a#(x1) -> b#(b(x1)) b#(b(c(x1))) -> a#(x1) -> a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) -> b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(c(b(b(x1)))) -> b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) -> b#(b(c(x1))) -> a#(x1) SCC Processor: #sccs: 1 #rules: 4 #arcs: 8/36 DPs: b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(c(b(b(x1)))) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 interpretation: [b#](x0) = [0 -&]x0 + [1], [-& 0 ] [1] [c](x0) = [0 1 ]x0 + [2], [a#](x0) = [0 1]x0 + [2], [-& 0 ] [1] [a](x0) = [0 1 ]x0 + [2], [-& 0 ] [0] [b](x0) = [0 -&]x0 + [0] orientation: b#(b(c(x1))) = [0 1]x1 + [2] >= [0 1]x1 + [2] = a#(x1) a#(x1) = [0 1]x1 + [2] >= [0 -&]x1 + [1] = b#(x1) a#(x1) = [0 1]x1 + [2] >= [-& 0 ]x1 + [1] = b#(b(x1)) a#(x1) = [0 1]x1 + [2] >= [-& 0 ]x1 + [1] = b#(c(b(b(x1)))) [-& 0 ] [1] [-& 0 ] [1] a(x1) = [0 1 ]x1 + [2] >= [0 1 ]x1 + [2] = c(b(c(b(b(x1))))) [-& 0 ] [1] [-& 0 ] [1] b(b(c(x1))) = [0 1 ]x1 + [2] >= [0 1 ]x1 + [2] = a(x1) [0 1] [2] c(c(x1)) = [1 2]x1 + [3] >= x1 = x1 problem: DPs: b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 Restore Modifier: DPs: b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 EDG Processor: DPs: b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 graph: b#(b(c(x1))) -> a#(x1) -> a#(x1) -> b#(x1) a#(x1) -> b#(x1) -> b#(b(c(x1))) -> a#(x1) Usable Rule Processor: DPs: b#(b(c(x1))) -> a#(x1) a#(x1) -> b#(x1) TRS: Arctic Interpretation Processor: dimension: 1 usable rules: interpretation: [b#](x0) = x0, [c](x0) = 8x0 + 8, [a#](x0) = x0, [b](x0) = x0 + 9 orientation: b#(b(c(x1))) = 8x1 + 9 >= x1 = a#(x1) a#(x1) = x1 >= x1 = b#(x1) problem: DPs: a#(x1) -> b#(x1) TRS: Restore Modifier: DPs: a#(x1) -> b#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 EDG Processor: DPs: a#(x1) -> b#(x1) TRS: a(x1) -> c(b(c(b(b(x1))))) b(b(c(x1))) -> a(x1) c(c(x1)) -> x1 graph: SCC Processor: #sccs: 0 #rules: 0 #arcs: 0/1