YES Problem: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) Proof: DP Processor: DPs: a#(c(x1)) -> b#(x1) a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) TDG Processor: DPs: a#(c(x1)) -> b#(x1) a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) graph: b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(x1)) b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(x1) b#(c(b(x1))) -> a#(c(x1)) -> a#(c(x1)) -> b#(x1) a#(c(x1)) -> b#(x1) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(b(b(x1))) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(b(x1)) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(x1) -> b#(c(b(x1))) -> a#(c(x1)) Arctic Interpretation Processor: dimension: 1 interpretation: [b#](x0) = x0 + 0, [a#](x0) = x0 + 0, [b](x0) = x0, [a](x0) = x0 + 0, [c](x0) = 1x0 + 8 orientation: a#(c(x1)) = 1x1 + 8 >= x1 + 0 = b#(x1) a#(x1) = x1 + 0 >= x1 + 0 = b#(x1) a#(x1) = x1 + 0 >= x1 + 0 = b#(b(x1)) a#(x1) = x1 + 0 >= x1 + 0 = b#(b(b(x1))) b#(c(b(x1))) = 1x1 + 8 >= 1x1 + 8 = a#(c(x1)) a(c(x1)) = 1x1 + 8 >= 1x1 + 8 = c(b(x1)) a(x1) = x1 + 0 >= x1 = b(b(b(x1))) b(c(b(x1))) = 1x1 + 8 >= 1x1 + 8 = a(c(x1)) problem: DPs: a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) EDG Processor: DPs: a#(x1) -> b#(x1) a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) graph: b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(x1) b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(x1)) b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(b(x1))) a#(x1) -> b#(b(b(x1))) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(b(x1)) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(x1) -> b#(c(b(x1))) -> a#(c(x1)) Matrix Interpretation Processor: dim=4 interpretation: [b#](x0) = [1 0 1 0]x0, [a#](x0) = [1 0 1 0]x0 + [1], [0 0 0 0] [1] [1 0 0 1] [0] [b](x0) = [0 0 1 0]x0 + [0] [0 1 0 0] [0], [0 0 0 0] [1] [1 0 0 1] [1] [a](x0) = [1 0 1 0]x0 + [0] [0 1 0 0] [1], [1 0 0 0] [1 1 0 1] [c](x0) = [0 1 1 1]x0 [0 1 0 1] orientation: a#(x1) = [1 0 1 0]x1 + [1] >= [1 0 1 0]x1 = b#(x1) a#(x1) = [1 0 1 0]x1 + [1] >= [0 0 1 0]x1 + [1] = b#(b(x1)) a#(x1) = [1 0 1 0]x1 + [1] >= [0 0 1 0]x1 + [1] = b#(b(b(x1))) b#(c(b(x1))) = [1 1 1 1]x1 + [1] >= [1 1 1 1]x1 + [1] = a#(c(x1)) [0 0 0 0] [1] [0 0 0 0] [1] [1 1 0 1] [1] [1 1 0 1] [1] a(c(x1)) = [1 1 1 1]x1 + [0] >= [1 1 1 1]x1 + [0] = c(b(x1)) [1 1 0 1] [1] [1 1 0 1] [0] [0 0 0 0] [1] [0 0 0 0] [1] [1 0 0 1] [1] [1 0 0 1] [1] a(x1) = [1 0 1 0]x1 + [0] >= [0 0 1 0]x1 + [0] = b(b(b(x1))) [0 1 0 0] [1] [0 1 0 0] [1] [0 0 0 0] [1] [0 0 0 0] [1] [1 1 0 1] [1] [1 1 0 1] [1] b(c(b(x1))) = [1 1 1 1]x1 + [0] >= [1 1 1 1]x1 + [0] = a(c(x1)) [1 1 0 1] [1] [1 1 0 1] [1] problem: DPs: a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) EDG Processor: DPs: a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) graph: b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(b(x1))) b#(c(b(x1))) -> a#(c(x1)) -> a#(x1) -> b#(b(x1)) a#(x1) -> b#(b(b(x1))) -> b#(c(b(x1))) -> a#(c(x1)) a#(x1) -> b#(b(x1)) -> b#(c(b(x1))) -> a#(c(x1)) Matrix Interpretation Processor: dim=4 interpretation: [b#](x0) = [0 0 1 0]x0, [a#](x0) = [0 0 1 0]x0 + [1], [0 0 0 0] [1] [0 0 0 1] [0] [b](x0) = [0 0 1 0]x0 + [0] [1 1 0 0] [0], [0 0 0 0] [1] [0 0 0 1] [1] [a](x0) = [1 0 1 0]x0 + [1] [1 1 0 0] [1], [0 0 0 0] [1 1 0 1] [c](x0) = [1 1 0 1]x0 [1 1 0 1] orientation: a#(x1) = [0 0 1 0]x1 + [1] >= [0 0 1 0]x1 = b#(b(x1)) a#(x1) = [0 0 1 0]x1 + [1] >= [0 0 1 0]x1 = b#(b(b(x1))) b#(c(b(x1))) = [1 1 0 1]x1 + [1] >= [1 1 0 1]x1 + [1] = a#(c(x1)) [0 0 0 0] [1] [0 0 0 0] [0] [1 1 0 1] [1] [1 1 0 1] [1] a(c(x1)) = [1 1 0 1]x1 + [1] >= [1 1 0 1]x1 + [1] = c(b(x1)) [1 1 0 1] [1] [1 1 0 1] [1] [0 0 0 0] [1] [0 0 0 0] [1] [0 0 0 1] [1] [0 0 0 1] [1] a(x1) = [1 0 1 0]x1 + [1] >= [0 0 1 0]x1 + [0] = b(b(b(x1))) [1 1 0 0] [1] [1 1 0 0] [1] [0 0 0 0] [1] [0 0 0 0] [1] [1 1 0 1] [1] [1 1 0 1] [1] b(c(b(x1))) = [1 1 0 1]x1 + [1] >= [1 1 0 1]x1 + [1] = a(c(x1)) [1 1 0 1] [1] [1 1 0 1] [1] problem: DPs: b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) EDG Processor: DPs: b#(c(b(x1))) -> a#(c(x1)) TRS: a(c(x1)) -> c(b(x1)) a(x1) -> b(b(b(x1))) b(c(b(x1))) -> a(c(x1)) graph: Qed