YES Problem: a(x1) -> x1 a(b(b(x1))) -> b(b(b(c(x1)))) c(b(x1)) -> a(a(x1)) Proof: String Reversal Processor: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) DP Processor: DPs: b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(b(b(x1))) b#(c(x1)) -> a#(x1) b#(c(x1)) -> a#(a(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) TDG Processor: DPs: b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(b(b(x1))) b#(c(x1)) -> a#(x1) b#(c(x1)) -> a#(a(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) graph: b#(b(a(x1))) -> b#(b(b(x1))) -> b#(c(x1)) -> a#(a(x1)) b#(b(a(x1))) -> b#(b(b(x1))) -> b#(c(x1)) -> a#(x1) b#(b(a(x1))) -> b#(b(b(x1))) -> b#(b(a(x1))) -> b#(b(b(x1))) b#(b(a(x1))) -> b#(b(b(x1))) -> b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(b(b(x1))) -> b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) -> b#(c(x1)) -> a#(a(x1)) b#(b(a(x1))) -> b#(b(x1)) -> b#(c(x1)) -> a#(x1) b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(b(b(x1))) b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(x1) -> b#(c(x1)) -> a#(a(x1)) b#(b(a(x1))) -> b#(x1) -> b#(c(x1)) -> a#(x1) b#(b(a(x1))) -> b#(x1) -> b#(b(a(x1))) -> b#(b(b(x1))) b#(b(a(x1))) -> b#(x1) -> b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(x1) -> b#(b(a(x1))) -> b#(x1) SCC Processor: #sccs: 1 #rules: 3 #arcs: 15/25 DPs: b#(b(a(x1))) -> b#(b(b(x1))) b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) Arctic Interpretation Processor: dimension: 3 usable rules: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) interpretation: [b#](x0) = [-& 0 -&]x0 + [0], [-& 0 -&] [0 ] [b](x0) = [-& -& 0 ]x0 + [-&] [0 -& -&] [0 ], [0 -& -&] [-&] [a](x0) = [0 0 -&]x0 + [-&] [1 0 0 ] [1 ], [1 0 0 ] [1] [c](x0) = [0 -& -&]x0 + [0] [0 0 -&] [0] orientation: b#(b(a(x1))) = [1 0 0]x1 + [1] >= [0 -& -&]x1 + [0] = b#(b(b(x1))) b#(b(a(x1))) = [1 0 0]x1 + [1] >= [-& 0 -&]x1 + [0] = b#(x1) b#(b(a(x1))) = [1 0 0]x1 + [1] >= [-& -& 0 ]x1 + [0] = b#(b(x1)) [0 -& -&] [-&] a(x1) = [0 0 -&]x1 + [-&] >= x1 = x1 [1 0 0 ] [1 ] [1 0 0 ] [1] [1 0 0 ] [1] b(b(a(x1))) = [0 -& -&]x1 + [0] >= [0 -& -&]x1 + [0] = c(b(b(b(x1)))) [0 0 -&] [0] [0 0 -&] [0] [0 -& -&] [0] [0 -& -&] [-&] b(c(x1)) = [0 0 -&]x1 + [0] >= [0 0 -&]x1 + [-&] = a(a(x1)) [1 0 0 ] [1] [1 0 0 ] [1 ] problem: DPs: b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) Restore Modifier: DPs: b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) EDG Processor: DPs: b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) graph: b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(b(x1)) b#(b(a(x1))) -> b#(x1) -> b#(b(a(x1))) -> b#(x1) b#(b(a(x1))) -> b#(x1) -> b#(b(a(x1))) -> b#(b(x1)) Arctic Interpretation Processor: dimension: 1 usable rules: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) interpretation: [b#](x0) = x0, [b](x0) = 1x0, [a](x0) = x0 + 0, [c](x0) = -1x0 + 0 orientation: b#(b(a(x1))) = 1x1 + 1 >= x1 = b#(x1) b#(b(a(x1))) = 1x1 + 1 >= 1x1 = b#(b(x1)) a(x1) = x1 + 0 >= x1 = x1 b(b(a(x1))) = 2x1 + 2 >= 2x1 + 0 = c(b(b(b(x1)))) b(c(x1)) = x1 + 1 >= x1 + 0 = a(a(x1)) problem: DPs: b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) Restore Modifier: DPs: b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) EDG Processor: DPs: b#(b(a(x1))) -> b#(b(x1)) TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) graph: b#(b(a(x1))) -> b#(b(x1)) -> b#(b(a(x1))) -> b#(b(x1)) Bounds Processor: bound: 0 enrichment: match-dp automaton: final states: {1} transitions: f50() -> 2* b0(5) -> 6* b0(4) -> 5* b0(2) -> 3* b{#,0}(3) -> 1* a0(16) -> 17* a0(15) -> 16* a0(18) -> 19* a0(19) -> 20* c0(6) -> 7* 19 -> 20,4 17 -> 15,5 7 -> 6,15,16,5,3 16 -> 6,17 2 -> 18* 6 -> 15* 20 -> 17,5,3 3 -> 4* 18 -> 19* 15 -> 16* problem: DPs: TRS: a(x1) -> x1 b(b(a(x1))) -> c(b(b(b(x1)))) b(c(x1)) -> a(a(x1)) Qed