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