YES Problem: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) Proof: DP Processor: DPs: a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> b#(a(a(a(x1)))) b#(a(x1)) -> a#(a(x1)) a#(a(x1)) -> b#(x1) a#(a(x1)) -> a#(c(b(x1))) TRS: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) TDG Processor: DPs: a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> b#(a(a(a(x1)))) b#(a(x1)) -> a#(a(x1)) a#(a(x1)) -> b#(x1) a#(a(x1)) -> a#(c(b(x1))) TRS: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) graph: b#(a(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(c(b(x1))) b#(a(x1)) -> a#(a(x1)) -> a#(a(x1)) -> b#(x1) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(a(x1)))) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(a(x1))) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1)) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> a#(a(x1)) a#(a(x1)) -> a#(c(b(x1))) -> a#(a(x1)) -> a#(c(b(x1))) a#(a(x1)) -> a#(c(b(x1))) -> a#(a(x1)) -> b#(x1) a#(a(x1)) -> a#(c(b(x1))) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(a(x1)) -> a#(c(b(x1))) -> a#(b(x1)) -> a#(a(a(x1))) a#(a(x1)) -> a#(c(b(x1))) -> a#(b(x1)) -> a#(a(x1)) a#(a(x1)) -> a#(c(b(x1))) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> b#(a(a(a(x1)))) -> b#(a(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) -> a#(a(x1)) -> a#(c(b(x1))) a#(b(x1)) -> a#(a(a(x1))) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(c(b(x1))) a#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(x1) -> a#(a(x1)) -> a#(c(b(x1))) a#(b(x1)) -> a#(x1) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(x1) EDG Processor: DPs: a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> b#(a(a(a(x1)))) b#(a(x1)) -> a#(a(x1)) a#(a(x1)) -> b#(x1) a#(a(x1)) -> a#(c(b(x1))) TRS: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) graph: b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1)) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(a(x1))) b#(a(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(a(x1)))) b#(a(x1)) -> a#(a(x1)) -> a#(a(x1)) -> b#(x1) b#(a(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(c(b(x1))) a#(a(x1)) -> b#(x1) -> b#(a(x1)) -> a#(a(x1)) a#(b(x1)) -> b#(a(a(a(x1)))) -> b#(a(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(a(a(x1))) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(a(a(x1))) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(a(a(x1))) -> a#(a(x1)) -> a#(c(b(x1))) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(a(x1)) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(a(x1)) -> a#(a(x1)) -> a#(c(b(x1))) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(x1) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(x1) -> a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(x1) -> a#(a(x1)) -> b#(x1) a#(b(x1)) -> a#(x1) -> a#(a(x1)) -> a#(c(b(x1))) SCC Processor: #sccs: 1 #rules: 6 #arcs: 26/49 DPs: b#(a(x1)) -> a#(a(x1)) a#(a(x1)) -> b#(x1) a#(b(x1)) -> b#(a(a(a(x1)))) a#(b(x1)) -> a#(a(a(x1))) a#(b(x1)) -> a#(a(x1)) a#(b(x1)) -> a#(x1) TRS: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) Matrix Interpretation Processor: dim=3 interpretation: [b#](x0) = [2 0 2]x0, [a#](x0) = [0 2 2]x0 + [1], [0 0 1] [1] [c](x0) = [0 0 0]x0 + [0] [0 0 0] [0], [0 1 0] [1] [a](x0) = [0 1 0]x0 + [0] [1 0 1] [0], [0 3 0] [3] [b](x0) = [0 3 0]x0 + [3] [1 0 1] [0] orientation: b#(a(x1)) = [2 2 2]x1 + [2] >= [2 2 2]x1 + [1] = a#(a(x1)) a#(a(x1)) = [2 2 2]x1 + [1] >= [2 0 2]x1 = b#(x1) a#(b(x1)) = [2 6 2]x1 + [7] >= [2 6 2]x1 + [6] = b#(a(a(a(x1)))) a#(b(x1)) = [2 6 2]x1 + [7] >= [2 4 2]x1 + [3] = a#(a(a(x1))) a#(b(x1)) = [2 6 2]x1 + [7] >= [2 2 2]x1 + [1] = a#(a(x1)) a#(b(x1)) = [2 6 2]x1 + [7] >= [0 2 2]x1 + [1] = a#(x1) [0 3 0] [4] [0 3 0] [3] a(b(x1)) = [0 3 0]x1 + [3] >= [0 3 0]x1 + [3] = b(a(a(a(x1)))) [1 3 1] [3] [1 3 1] [3] [0 3 0] [3] [0 1 0] [1] b(a(x1)) = [0 3 0]x1 + [3] >= [0 1 0]x1 + [0] = a(a(x1)) [1 1 1] [1] [1 1 1] [1] [0 1 0] [1] [0 0 0] [1] a(a(x1)) = [0 1 0]x1 + [0] >= [0 0 0]x1 + [0] = a(c(b(x1))) [1 1 1] [1] [1 0 1] [1] problem: DPs: TRS: a(b(x1)) -> b(a(a(a(x1)))) b(a(x1)) -> a(a(x1)) a(a(x1)) -> a(c(b(x1))) Qed