YES Problem: a__f(X) -> g(h(f(X))) mark(f(X)) -> a__f(mark(X)) mark(g(X)) -> g(X) mark(h(X)) -> h(mark(X)) a__f(X) -> f(X) Proof: Arctic Interpretation Processor: dimension: 2 interpretation: [0 2] [mark](x0) = [0 1]x0, [0 -&] [g](x0) = [0 -&]x0, [h](x0) = x0, [0 -&] [f](x0) = [0 1 ]x0, [0 0] [a__f](x0) = [0 1]x0 orientation: [0 0] [0 -&] a__f(X) = [0 1]X >= [0 -&]X = g(h(f(X))) [2 3] [0 2] mark(f(X)) = [1 2]X >= [1 2]X = a__f(mark(X)) [2 -&] [0 -&] mark(g(X)) = [1 -&]X >= [0 -&]X = g(X) [0 2] [0 2] mark(h(X)) = [0 1]X >= [0 1]X = h(mark(X)) [0 0] [0 -&] a__f(X) = [0 1]X >= [0 1 ]X = f(X) problem: a__f(X) -> g(h(f(X))) mark(f(X)) -> a__f(mark(X)) mark(h(X)) -> h(mark(X)) a__f(X) -> f(X) String Reversal Processor: a__f(X) -> f(h(g(X))) f(mark(X)) -> mark(a__f(X)) h(mark(X)) -> mark(h(X)) a__f(X) -> f(X) Bounds Processor: bound: 1 enrichment: match automaton: final states: {9,7,5,1} transitions: f50() -> 2* f0(2) -> 9* f0(4) -> 1* h0(2) -> 8* h0(3) -> 4* g0(2) -> 3* mark0(6) -> 5* mark0(8) -> 7* a__f0(2) -> 6* f1(16) -> 17* f1(18) -> 19* h1(15) -> 16* g1(14) -> 15* 2 -> 18,14 5 -> 19,9,6 7 -> 8* 17 -> 6* 19 -> 6* problem: Qed