YES Problem: a(b(c(x1))) -> b(x1) c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) Proof: Arctic Interpretation Processor: dimension: 2 interpretation: [3 -&] [a](x0) = [-& -&]x0, [1 -&] [b](x0) = [-& -&]x0, [1 -&] [c](x0) = [-& 0 ]x0 orientation: [5 -&] [1 -&] a(b(c(x1))) = [-& -&]x1 >= [-& -&]x1 = b(x1) [3 -&] [3 -&] c(b(b(x1))) = [-& -&]x1 >= [-& -&]x1 = a(x1) [1 -&] [1 -&] c(x1) = [-& 0 ]x1 >= [-& -&]x1 = b(x1) [6 -&] [6 -&] a(a(x1)) = [-& -&]x1 >= [-& -&]x1 = c(b(a(c(x1)))) problem: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) DP Processor: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(x1) a#(a(x1)) -> a#(c(x1)) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) TDG Processor: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(x1) a#(a(x1)) -> a#(c(x1)) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) graph: a#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> c#(b(a(c(x1)))) a#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> a#(c(x1)) a#(a(x1)) -> a#(c(x1)) -> a#(a(x1)) -> c#(x1) a#(a(x1)) -> c#(b(a(c(x1)))) -> c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(x1) -> c#(b(b(x1))) -> a#(x1) c#(b(b(x1))) -> a#(x1) -> a#(a(x1)) -> c#(b(a(c(x1)))) c#(b(b(x1))) -> a#(x1) -> a#(a(x1)) -> a#(c(x1)) c#(b(b(x1))) -> a#(x1) -> a#(a(x1)) -> c#(x1) Arctic Interpretation Processor: dimension: 2 usable rules: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) interpretation: [a#](x0) = [2 3]x0 + [0], [c#](x0) = [0 2]x0, [1 2 ] [2] [a](x0) = [1 -&]x0 + [1], [0 1] [1] [b](x0) = [0 0]x0 + [0], [0 1] [1] [c](x0) = [0 0]x0 + [0] orientation: c#(b(b(x1))) = [2 3]x1 + [3] >= [2 3]x1 + [0] = a#(x1) a#(a(x1)) = [4 4]x1 + [4] >= [0 2]x1 = c#(x1) a#(a(x1)) = [4 4]x1 + [4] >= [3 3]x1 + [3] = a#(c(x1)) a#(a(x1)) = [4 4]x1 + [4] >= [4 4]x1 + [4] = c#(b(a(c(x1)))) [1 2] [2] [1 2 ] [2] c(b(b(x1))) = [1 1]x1 + [1] >= [1 -&]x1 + [1] = a(x1) [0 1] [1] [0 1] [1] c(x1) = [0 0]x1 + [0] >= [0 0]x1 + [0] = b(x1) [3 3] [3] [3 3] [3] a(a(x1)) = [2 3]x1 + [3] >= [2 3]x1 + [3] = c(b(a(c(x1)))) problem: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) Restore Modifier: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) EDG Processor: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) graph: a#(a(x1)) -> c#(b(a(c(x1)))) -> c#(b(b(x1))) -> a#(x1) c#(b(b(x1))) -> a#(x1) -> a#(a(x1)) -> c#(b(a(c(x1)))) CDG Processor: DPs: c#(b(b(x1))) -> a#(x1) a#(a(x1)) -> c#(b(a(c(x1)))) TRS: c(b(b(x1))) -> a(x1) c(x1) -> b(x1) a(a(x1)) -> c(b(a(c(x1)))) graph: a#(a(x1)) -> c#(b(a(c(x1)))) -> c#(b(b(x1))) -> a#(x1) SCC Processor: #sccs: 0 #rules: 0 #arcs: 1/4