YES Problem: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) Proof: DP Processor: DPs: a#(b(x1)) -> c#(x1) c#(c(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(a(c(x1))) c#(c(x1)) -> b#(a(a(c(x1)))) c#(c(x1)) -> b#(b(a(a(c(x1))))) TRS: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) TDG Processor: DPs: a#(b(x1)) -> c#(x1) c#(c(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(a(c(x1))) c#(c(x1)) -> b#(a(a(c(x1)))) c#(c(x1)) -> b#(b(a(a(c(x1))))) TRS: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) graph: c#(c(x1)) -> a#(c(x1)) -> a#(b(x1)) -> c#(x1) c#(c(x1)) -> a#(a(c(x1))) -> a#(b(x1)) -> c#(x1) a#(b(x1)) -> c#(x1) -> c#(c(x1)) -> b#(b(a(a(c(x1))))) a#(b(x1)) -> c#(x1) -> c#(c(x1)) -> b#(a(a(c(x1)))) a#(b(x1)) -> c#(x1) -> c#(c(x1)) -> a#(a(c(x1))) a#(b(x1)) -> c#(x1) -> c#(c(x1)) -> a#(c(x1)) SCC Processor: #sccs: 1 #rules: 3 #arcs: 6/25 DPs: c#(c(x1)) -> a#(c(x1)) a#(b(x1)) -> c#(x1) c#(c(x1)) -> a#(a(c(x1))) TRS: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) Arctic Interpretation Processor: dimension: 2 interpretation: [c#](x0) = [0 -4]x0 + [0], [a#](x0) = [-& 0 ]x0 + [0], [1 0] [0 ] [c](x0) = [1 0]x0 + [-&], [0 -&] [-3] [b](x0) = [1 0 ]x0 + [1 ], [0 0 ] [0 ] [a](x0) = [-& 0 ]x0 + [-&] orientation: c#(c(x1)) = [1 0]x1 + [0] >= [1 0]x1 + [0] = a#(c(x1)) a#(b(x1)) = [1 0]x1 + [1] >= [0 -4]x1 + [0] = c#(x1) c#(c(x1)) = [1 0]x1 + [0] >= [1 0]x1 + [0] = a#(a(c(x1))) [0 0 ] [0 ] a(x1) = [-& 0 ]x1 + [-&] >= x1 = x1 [1 0] [1] [1 0] [0 ] a(b(x1)) = [1 0]x1 + [1] >= [1 0]x1 + [-&] = c(x1) [0 -&] [-3] b(x1) = [1 0 ]x1 + [1 ] >= x1 = x1 [2 1] [1] [1 0] [0] c(c(x1)) = [2 1]x1 + [1] >= [2 1]x1 + [1] = b(b(a(a(c(x1))))) problem: DPs: c#(c(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(a(c(x1))) TRS: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) EDG Processor: DPs: c#(c(x1)) -> a#(c(x1)) c#(c(x1)) -> a#(a(c(x1))) TRS: a(x1) -> x1 a(b(x1)) -> c(x1) b(x1) -> x1 c(c(x1)) -> b(b(a(a(c(x1))))) graph: Qed