YES Problem: +(x,0()) -> x +(x,s(y)) -> s(+(x,y)) +(0(),y) -> y +(s(x),y) -> s(+(x,y)) +(x,+(y,z)) -> +(+(x,y),z) f(g(f(x))) -> f(h(s(0()),x)) f(g(h(x,y))) -> f(h(s(x),y)) f(h(x,h(y,z))) -> f(h(+(x,y),z)) Proof: DP Processor: DPs: +#(x,s(y)) -> +#(x,y) +#(s(x),y) -> +#(x,y) +#(x,+(y,z)) -> +#(x,y) +#(x,+(y,z)) -> +#(+(x,y),z) f#(g(f(x))) -> f#(h(s(0()),x)) f#(g(h(x,y))) -> f#(h(s(x),y)) f#(h(x,h(y,z))) -> +#(x,y) f#(h(x,h(y,z))) -> f#(h(+(x,y),z)) TRS: +(x,0()) -> x +(x,s(y)) -> s(+(x,y)) +(0(),y) -> y +(s(x),y) -> s(+(x,y)) +(x,+(y,z)) -> +(+(x,y),z) f(g(f(x))) -> f(h(s(0()),x)) f(g(h(x,y))) -> f(h(s(x),y)) f(h(x,h(y,z))) -> f(h(+(x,y),z)) Matrix Interpretation Processor: dim=1 interpretation: [f#](x0) = 3x0 + 1/2, [+#](x0, x1) = 1/2x0 + 3/2x1, [h](x0, x1) = 1/2x0 + 3x1 + 2, [g](x0) = x0 + 3, [f](x0) = 3x0 + 2, [s](x0) = x0 + 3, [+](x0, x1) = x0 + 3x1 + 3, [0] = 0 orientation: +#(x,s(y)) = 1/2x + 3/2y + 9/2 >= 1/2x + 3/2y = +#(x,y) +#(s(x),y) = 1/2x + 3/2y + 3/2 >= 1/2x + 3/2y = +#(x,y) +#(x,+(y,z)) = 1/2x + 3/2y + 9/2z + 9/2 >= 1/2x + 3/2y = +#(x,y) +#(x,+(y,z)) = 1/2x + 3/2y + 9/2z + 9/2 >= 1/2x + 3/2y + 3/2z + 3/2 = +#(+(x,y),z) f#(g(f(x))) = 9x + 31/2 >= 9x + 11 = f#(h(s(0()),x)) f#(g(h(x,y))) = 3/2x + 9y + 31/2 >= 3/2x + 9y + 11 = f#(h(s(x),y)) f#(h(x,h(y,z))) = 3/2x + 9/2y + 27z + 49/2 >= 1/2x + 3/2y = +#(x,y) f#(h(x,h(y,z))) = 3/2x + 9/2y + 27z + 49/2 >= 3/2x + 9/2y + 9z + 11 = f#(h(+(x,y),z)) +(x,0()) = x + 3 >= x = x +(x,s(y)) = x + 3y + 12 >= x + 3y + 6 = s(+(x,y)) +(0(),y) = 3y + 3 >= y = y +(s(x),y) = x + 3y + 6 >= x + 3y + 6 = s(+(x,y)) +(x,+(y,z)) = x + 3y + 9z + 12 >= x + 3y + 3z + 6 = +(+(x,y),z) f(g(f(x))) = 9x + 17 >= 9x + 25/2 = f(h(s(0()),x)) f(g(h(x,y))) = 3/2x + 9y + 17 >= 3/2x + 9y + 25/2 = f(h(s(x),y)) f(h(x,h(y,z))) = 3/2x + 9/2y + 27z + 26 >= 3/2x + 9/2y + 9z + 25/2 = f(h(+(x,y),z)) problem: DPs: TRS: +(x,0()) -> x +(x,s(y)) -> s(+(x,y)) +(0(),y) -> y +(s(x),y) -> s(+(x,y)) +(x,+(y,z)) -> +(+(x,y),z) f(g(f(x))) -> f(h(s(0()),x)) f(g(h(x,y))) -> f(h(s(x),y)) f(h(x,h(y,z))) -> f(h(+(x,y),z)) Qed