YES Problem: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) Proof: DP Processor: DPs: a#(c(x1)) -> b#(c(x1)) b#(c(x1)) -> b#(x1) b#(c(x1)) -> a#(b(x1)) TRS: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) TDG Processor: DPs: a#(c(x1)) -> b#(c(x1)) b#(c(x1)) -> b#(x1) b#(c(x1)) -> a#(b(x1)) TRS: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) graph: b#(c(x1)) -> b#(x1) -> b#(c(x1)) -> a#(b(x1)) b#(c(x1)) -> b#(x1) -> b#(c(x1)) -> b#(x1) b#(c(x1)) -> a#(b(x1)) -> a#(c(x1)) -> b#(c(x1)) a#(c(x1)) -> b#(c(x1)) -> b#(c(x1)) -> a#(b(x1)) a#(c(x1)) -> b#(c(x1)) -> b#(c(x1)) -> b#(x1) Arctic Interpretation Processor: dimension: 1 interpretation: [b#](x0) = -4x0 + 8, [a#](x0) = x0 + 0, [c](x0) = 4x0 + 12, [a](x0) = 4x0 + 0, [b](x0) = -4x0 + 1 orientation: a#(c(x1)) = 4x1 + 12 >= x1 + 8 = b#(c(x1)) b#(c(x1)) = x1 + 8 >= -4x1 + 8 = b#(x1) b#(c(x1)) = x1 + 8 >= -4x1 + 1 = a#(b(x1)) a(b(x1)) = x1 + 5 >= x1 = x1 a(c(x1)) = 8x1 + 16 >= 8x1 + 16 = c(c(b(c(x1)))) b(c(x1)) = x1 + 8 >= x1 + 5 = a(b(x1)) problem: DPs: b#(c(x1)) -> b#(x1) TRS: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) EDG Processor: DPs: b#(c(x1)) -> b#(x1) TRS: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) graph: b#(c(x1)) -> b#(x1) -> b#(c(x1)) -> b#(x1) CDG Processor: DPs: b#(c(x1)) -> b#(x1) TRS: a(b(x1)) -> x1 a(c(x1)) -> c(c(b(c(x1)))) b(c(x1)) -> a(b(x1)) graph: Qed