YES Problem: t(f(x1)) -> t(c(n(x1))) n(f(x1)) -> f(n(x1)) o(f(x1)) -> f(o(x1)) n(s(x1)) -> f(s(x1)) o(s(x1)) -> f(s(x1)) c(f(x1)) -> f(c(x1)) c(n(x1)) -> n(c(x1)) c(o(x1)) -> o(c(x1)) c(o(x1)) -> o(x1) Proof: Arctic Interpretation Processor: dimension: 2 interpretation: [3 -&] [s](x0) = [3 0 ]x0, [3 2 ] [o](x0) = [-& 1 ]x0, [0 -&] [c](x0) = [0 -&]x0, [0 0] [n](x0) = [0 0]x0, [0 0] [t](x0) = [0 0]x0, [0 0 ] [f](x0) = [-& 0 ]x0 orientation: [0 0] [0 0] t(f(x1)) = [0 0]x1 >= [0 0]x1 = t(c(n(x1))) [0 0] [0 0] n(f(x1)) = [0 0]x1 >= [0 0]x1 = f(n(x1)) [3 3 ] [3 2 ] o(f(x1)) = [-& 1 ]x1 >= [-& 1 ]x1 = f(o(x1)) [3 0] [3 0] n(s(x1)) = [3 0]x1 >= [3 0]x1 = f(s(x1)) [6 2] [3 0] o(s(x1)) = [4 1]x1 >= [3 0]x1 = f(s(x1)) [0 0] [0 -&] c(f(x1)) = [0 0]x1 >= [0 -&]x1 = f(c(x1)) [0 0] [0 -&] c(n(x1)) = [0 0]x1 >= [0 -&]x1 = n(c(x1)) [3 2] [3 -&] c(o(x1)) = [3 2]x1 >= [1 -&]x1 = o(c(x1)) [3 2] [3 2 ] c(o(x1)) = [3 2]x1 >= [-& 1 ]x1 = o(x1) problem: t(f(x1)) -> t(c(n(x1))) n(f(x1)) -> f(n(x1)) o(f(x1)) -> f(o(x1)) n(s(x1)) -> f(s(x1)) c(f(x1)) -> f(c(x1)) c(n(x1)) -> n(c(x1)) c(o(x1)) -> o(c(x1)) c(o(x1)) -> o(x1) String Reversal Processor: f(t(x1)) -> n(c(t(x1))) f(n(x1)) -> n(f(x1)) f(o(x1)) -> o(f(x1)) s(n(x1)) -> s(f(x1)) f(c(x1)) -> c(f(x1)) n(c(x1)) -> c(n(x1)) o(c(x1)) -> c(o(x1)) o(c(x1)) -> o(x1) Matrix Interpretation Processor: dim=3 interpretation: [1 1 0] [s](x0) = [1 1 0]x0 [0 0 0] , [1 0 0] [0] [o](x0) = [1 0 0]x0 + [1] [0 0 0] [0], [1 0 1] [c](x0) = [0 0 0]x0 [0 0 0] , [1 0 1] [0] [n](x0) = [0 1 0]x0 + [1] [0 0 0] [0], [1 0 1] [0] [t](x0) = [1 1 0]x0 + [1] [0 0 0] [0], [1 0 0] [f](x0) = [0 1 0]x0 [0 0 0] orientation: [1 0 1] [0] [1 0 1] [0] f(t(x1)) = [1 1 0]x1 + [1] >= [0 0 0]x1 + [1] = n(c(t(x1))) [0 0 0] [0] [0 0 0] [0] [1 0 1] [0] [1 0 0] [0] f(n(x1)) = [0 1 0]x1 + [1] >= [0 1 0]x1 + [1] = n(f(x1)) [0 0 0] [0] [0 0 0] [0] [1 0 0] [0] [1 0 0] [0] f(o(x1)) = [1 0 0]x1 + [1] >= [1 0 0]x1 + [1] = o(f(x1)) [0 0 0] [0] [0 0 0] [0] [1 1 1] [1] [1 1 0] s(n(x1)) = [1 1 1]x1 + [1] >= [1 1 0]x1 = s(f(x1)) [0 0 0] [0] [0 0 0] [1 0 1] [1 0 0] f(c(x1)) = [0 0 0]x1 >= [0 0 0]x1 = c(f(x1)) [0 0 0] [0 0 0] [1 0 1] [0] [1 0 1] n(c(x1)) = [0 0 0]x1 + [1] >= [0 0 0]x1 = c(n(x1)) [0 0 0] [0] [0 0 0] [1 0 1] [0] [1 0 0] o(c(x1)) = [1 0 1]x1 + [1] >= [0 0 0]x1 = c(o(x1)) [0 0 0] [0] [0 0 0] [1 0 1] [0] [1 0 0] [0] o(c(x1)) = [1 0 1]x1 + [1] >= [1 0 0]x1 + [1] = o(x1) [0 0 0] [0] [0 0 0] [0] problem: f(t(x1)) -> n(c(t(x1))) f(n(x1)) -> n(f(x1)) f(o(x1)) -> o(f(x1)) f(c(x1)) -> c(f(x1)) n(c(x1)) -> c(n(x1)) o(c(x1)) -> c(o(x1)) o(c(x1)) -> o(x1) Arctic Interpretation Processor: dimension: 1 interpretation: [o](x0) = 14x0, [c](x0) = 1x0, [n](x0) = 10x0, [t](x0) = 5x0, [f](x0) = 11x0 orientation: f(t(x1)) = 16x1 >= 16x1 = n(c(t(x1))) f(n(x1)) = 21x1 >= 21x1 = n(f(x1)) f(o(x1)) = 25x1 >= 25x1 = o(f(x1)) f(c(x1)) = 12x1 >= 12x1 = c(f(x1)) n(c(x1)) = 11x1 >= 11x1 = c(n(x1)) o(c(x1)) = 15x1 >= 15x1 = c(o(x1)) o(c(x1)) = 15x1 >= 14x1 = o(x1) problem: f(t(x1)) -> n(c(t(x1))) f(n(x1)) -> n(f(x1)) f(o(x1)) -> o(f(x1)) f(c(x1)) -> c(f(x1)) n(c(x1)) -> c(n(x1)) o(c(x1)) -> c(o(x1)) Arctic Interpretation Processor: dimension: 1 interpretation: [o](x0) = 8x0, [c](x0) = x0, [n](x0) = x0, [t](x0) = 14x0, [f](x0) = 2x0 orientation: f(t(x1)) = 16x1 >= 14x1 = n(c(t(x1))) f(n(x1)) = 2x1 >= 2x1 = n(f(x1)) f(o(x1)) = 10x1 >= 10x1 = o(f(x1)) f(c(x1)) = 2x1 >= 2x1 = c(f(x1)) n(c(x1)) = x1 >= x1 = c(n(x1)) o(c(x1)) = 8x1 >= 8x1 = c(o(x1)) problem: f(n(x1)) -> n(f(x1)) f(o(x1)) -> o(f(x1)) f(c(x1)) -> c(f(x1)) n(c(x1)) -> c(n(x1)) o(c(x1)) -> c(o(x1)) KBO Processor: weight function: w0 = 1 w(o) = w(c) = w(n) = w(f) = 1 precedence: f > o ~ n > c problem: Qed