YES Problem: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) Proof: DP Processor: DPs: a#(x1) -> c#(x1) a#(x1) -> b#(c(x1)) c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) c#(c(b(x1))) -> c#(a(c(x1))) c#(c(b(x1))) -> b#(c(a(c(x1)))) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) TDG Processor: DPs: a#(x1) -> c#(x1) a#(x1) -> b#(c(x1)) c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) c#(c(b(x1))) -> c#(a(c(x1))) c#(c(b(x1))) -> b#(c(a(c(x1)))) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) graph: c#(c(b(x1))) -> c#(a(c(x1))) -> c#(c(b(x1))) -> b#(c(a(c(x1)))) c#(c(b(x1))) -> c#(a(c(x1))) -> c#(c(b(x1))) -> c#(a(c(x1))) c#(c(b(x1))) -> c#(a(c(x1))) -> c#(c(b(x1))) -> a#(c(x1)) c#(c(b(x1))) -> c#(a(c(x1))) -> c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> b#(c(a(c(x1)))) c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> c#(a(c(x1))) c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> a#(c(x1)) c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(c(x1)) c#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> c#(x1) a#(x1) -> c#(x1) -> c#(c(b(x1))) -> b#(c(a(c(x1)))) a#(x1) -> c#(x1) -> c#(c(b(x1))) -> c#(a(c(x1))) a#(x1) -> c#(x1) -> c#(c(b(x1))) -> a#(c(x1)) a#(x1) -> c#(x1) -> c#(c(b(x1))) -> c#(x1) SCC Processor: #sccs: 1 #rules: 4 #arcs: 14/36 DPs: c#(c(b(x1))) -> c#(a(c(x1))) c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) a#(x1) -> c#(x1) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) interpretation: [c#](x0) = [2 0]x0 + [0], [-& 0 ] [0] [c](x0) = [0 -&]x0 + [1], [a#](x0) = [3 1]x0 + [2], [0 -&] [1] [a](x0) = [1 0 ]x0 + [2], [-& 0 ] [1] [b](x0) = [0 1 ]x0 + [2] orientation: c#(c(b(x1))) = [2 3]x1 + [4] >= [0 2]x1 + [3] = c#(a(c(x1))) c#(c(b(x1))) = [2 3]x1 + [4] >= [2 0]x1 + [0] = c#(x1) c#(c(b(x1))) = [2 3]x1 + [4] >= [1 3]x1 + [3] = a#(c(x1)) a#(x1) = [3 1]x1 + [2] >= [2 0]x1 + [0] = c#(x1) [0 -&] [1] [0 -&] [1] a(x1) = [1 0 ]x1 + [2] >= [1 0 ]x1 + [2] = b(c(x1)) [0 1] [2] b(b(x1)) = [1 2]x1 + [3] >= x1 = x1 [-& 0 ] [1] [-& 0 ] [1] c(c(b(x1))) = [0 1 ]x1 + [2] >= [0 1 ]x1 + [2] = b(c(a(c(x1)))) problem: DPs: c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) Restore Modifier: DPs: c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) EDG Processor: DPs: c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> a#(c(x1)) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) graph: c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> c#(x1) c#(c(b(x1))) -> c#(x1) -> c#(c(b(x1))) -> a#(c(x1)) SCC Processor: #sccs: 1 #rules: 1 #arcs: 2/4 DPs: c#(c(b(x1))) -> c#(x1) TRS: a(x1) -> b(c(x1)) b(b(x1)) -> x1 c(c(b(x1))) -> b(c(a(c(x1)))) Usable Rule Processor: DPs: c#(c(b(x1))) -> c#(x1) TRS: Arctic Interpretation Processor: dimension: 1 usable rules: interpretation: [c#](x0) = x0, [c](x0) = x0 + 0, [b](x0) = 1x0 + 13 orientation: c#(c(b(x1))) = 1x1 + 13 >= x1 = c#(x1) problem: DPs: TRS: Qed