YES Problem: a(x1) -> x1 a(a(b(x1))) -> c(c(b(a(x1)))) b(c(x1)) -> a(b(x1)) Proof: String Reversal Processor: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) DP Processor: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) b#(a(a(x1))) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) c#(b(x1)) -> b#(a(x1)) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) TDG Processor: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) b#(a(a(x1))) -> a#(b(c(c(x1)))) c#(b(x1)) -> a#(x1) c#(b(x1)) -> b#(a(x1)) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) graph: c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> a#(b(c(c(x1)))) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> b#(c(c(x1))) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> c#(c(x1)) c#(b(x1)) -> b#(a(x1)) -> b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) -> c#(b(x1)) -> b#(a(x1)) b#(a(a(x1))) -> c#(c(x1)) -> c#(b(x1)) -> a#(x1) b#(a(a(x1))) -> c#(x1) -> c#(b(x1)) -> b#(a(x1)) b#(a(a(x1))) -> c#(x1) -> c#(b(x1)) -> a#(x1) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> a#(b(c(c(x1)))) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> b#(c(c(x1))) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> c#(x1) SCC Processor: #sccs: 1 #rules: 4 #arcs: 12/36 DPs: c#(b(x1)) -> b#(a(x1)) b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) Arctic Interpretation Processor: dimension: 2 usable rules: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) interpretation: [c#](x0) = [0 0]x0 + [0], [b#](x0) = [0 0]x0 + [0], [0 0] [0] [c](x0) = [0 0]x0 + [0], [1 0 ] [-&] [b](x0) = [-& 1 ]x0 + [1 ], [0 0] [-&] [a](x0) = [0 0]x0 + [0 ] orientation: c#(b(x1)) = [1 1]x1 + [1] >= [0 0]x1 + [0] = b#(a(x1)) b#(a(a(x1))) = [0 0]x1 + [0] >= [0 0]x1 + [0] = c#(x1) b#(a(a(x1))) = [0 0]x1 + [0] >= [0 0]x1 + [0] = c#(c(x1)) b#(a(a(x1))) = [0 0]x1 + [0] >= [0 0]x1 + [0] = b#(c(c(x1))) [0 0] [-&] a(x1) = [0 0]x1 + [0 ] >= x1 = x1 [1 1] [1] [1 1] [1] b(a(a(x1))) = [1 1]x1 + [1] >= [1 1]x1 + [1] = a(b(c(c(x1)))) [1 1] [1] [1 1] [0] c(b(x1)) = [1 1]x1 + [1] >= [1 1]x1 + [1] = b(a(x1)) problem: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) Restore Modifier: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) EDG Processor: DPs: b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) graph: b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> c#(x1) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> c#(c(x1)) b#(a(a(x1))) -> b#(c(c(x1))) -> b#(a(a(x1))) -> b#(c(c(x1))) SCC Processor: #sccs: 1 #rules: 1 #arcs: 3/9 DPs: b#(a(a(x1))) -> b#(c(c(x1))) TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) Bounds Processor: bound: 1 enrichment: match-dp automaton: final states: {5} transitions: b{#,0}(7) -> 5* a0(2) -> 2* a0(1) -> 2* a0(3) -> 2* c0(2) -> 1* c0(4) -> 6* c0(6) -> 7* c0(1) -> 1* c0(3) -> 1* b0(2) -> 3* b0(1) -> 3* b0(3) -> 3* b{#,1}(14) -> 15* c1(50) -> 51* c1(35) -> 36* c1(12) -> 13* c1(34) -> 35* c1(13) -> 14* b1(22) -> 23* b1(17) -> 18* b1(29) -> 30* b1(36) -> 37* a1(55) -> 56* a1(37) -> 38* a1(61) -> 62* a1(46) -> 47* a1(16) -> 17* a1(28) -> 29* a1(23) -> 24* 1 -> 2,4 2 -> 16,12,3,4 3 -> 7,6,1,2,4 14 -> 22* 15 -> 5* 16 -> 34,17 17 -> 28* 18 -> 51,35,13 22 -> 46* 23 -> 24,13 24 -> 18,13 28 -> 29* 29 -> 61,13,51 30 -> 36,14 36 -> 55* 37 -> 50,38,14 38 -> 30,14,22 46 -> 47,29 47 -> 29* 51 -> 35* 55 -> 56,17,28 56 -> 17* 61 -> 62,29,13,51 62 -> 29* problem: DPs: TRS: a(x1) -> x1 b(a(a(x1))) -> a(b(c(c(x1)))) c(b(x1)) -> b(a(x1)) Qed