YES Problem: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) Proof: DP Processor: DPs: a#(a(x1)) -> c#(x1) a#(a(x1)) -> c#(c(x1)) a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) c#(b(x1)) -> a#(a(x1)) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) TDG Processor: DPs: a#(a(x1)) -> c#(x1) a#(a(x1)) -> c#(c(x1)) a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) c#(b(x1)) -> a#(a(x1)) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) graph: c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> c#(x1) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> c#(x1) a#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(a(x1)) a#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(x1) a#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(a(x1)) a#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(x1) a#(a(x1)) -> a#(b(c(c(x1)))) -> a#(a(x1)) -> a#(b(c(c(x1)))) a#(a(x1)) -> a#(b(c(c(x1)))) -> a#(a(x1)) -> c#(c(x1)) a#(a(x1)) -> a#(b(c(c(x1)))) -> a#(a(x1)) -> c#(x1) EDG Processor: DPs: a#(a(x1)) -> c#(x1) a#(a(x1)) -> c#(c(x1)) a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) c#(b(x1)) -> a#(a(x1)) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) graph: c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> c#(x1) c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> c#(x1) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(x1) -> a#(a(x1)) -> a#(b(c(c(x1)))) a#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(x1) a#(a(x1)) -> c#(c(x1)) -> c#(b(x1)) -> a#(a(x1)) a#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(x1) a#(a(x1)) -> c#(x1) -> c#(b(x1)) -> a#(a(x1)) SCC Processor: #sccs: 1 #rules: 4 #arcs: 10/25 DPs: c#(b(x1)) -> a#(a(x1)) a#(a(x1)) -> c#(c(x1)) c#(b(x1)) -> a#(x1) a#(a(x1)) -> c#(x1) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) Arctic Interpretation Processor: dimension: 2 interpretation: [c#](x0) = [0 3]x0 + [0], [a#](x0) = [3 1]x0, [1 0] [1] [b](x0) = [2 1]x0 + [2], [-& 0 ] [0] [c](x0) = [0 -&]x0 + [0], [1 0 ] [1] [a](x0) = [0 -&]x0 + [0] orientation: c#(b(x1)) = [5 4]x1 + [5] >= [4 3]x1 + [4] = a#(a(x1)) a#(a(x1)) = [4 3]x1 + [4] >= [3 0]x1 + [3] = c#(c(x1)) c#(b(x1)) = [5 4]x1 + [5] >= [3 1]x1 = a#(x1) a#(a(x1)) = [4 3]x1 + [4] >= [0 3]x1 + [0] = c#(x1) [2 1] [2] [2 1] [2] a(a(x1)) = [1 0]x1 + [1] >= [1 0]x1 + [1] = a(b(c(c(x1)))) [0 -&] [0] c(a(x1)) = [1 0 ]x1 + [1] >= x1 = x1 [2 1] [2] [2 1] [2] c(b(x1)) = [1 0]x1 + [1] >= [1 0]x1 + [1] = a(a(x1)) problem: DPs: a#(a(x1)) -> c#(x1) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) EDG Processor: DPs: a#(a(x1)) -> c#(x1) TRS: a(a(x1)) -> a(b(c(c(x1)))) c(a(x1)) -> x1 c(b(x1)) -> a(a(x1)) graph: Qed