YES Problem: g(0(),f(x,x)) -> x g(x,s(y)) -> g(f(x,y),0()) g(s(x),y) -> g(f(x,y),0()) g(f(x,y),0()) -> f(g(x,0()),g(y,0())) Proof: DP Processor: DPs: g#(x,s(y)) -> g#(f(x,y),0()) g#(s(x),y) -> g#(f(x,y),0()) g#(f(x,y),0()) -> g#(y,0()) g#(f(x,y),0()) -> g#(x,0()) TRS: g(0(),f(x,x)) -> x g(x,s(y)) -> g(f(x,y),0()) g(s(x),y) -> g(f(x,y),0()) g(f(x,y),0()) -> f(g(x,0()),g(y,0())) Matrix Interpretation Processor: dim=1 interpretation: [g#](x0, x1) = x0 + 4x1, [s](x0) = 2x0 + 2, [g](x0, x1) = x0 + 4x1, [f](x0, x1) = x0 + 4x1 + 1, [0] = 0 orientation: g#(x,s(y)) = x + 8y + 8 >= x + 4y + 1 = g#(f(x,y),0()) g#(s(x),y) = 2x + 4y + 2 >= x + 4y + 1 = g#(f(x,y),0()) g#(f(x,y),0()) = x + 4y + 1 >= y = g#(y,0()) g#(f(x,y),0()) = x + 4y + 1 >= x = g#(x,0()) g(0(),f(x,x)) = 20x + 4 >= x = x g(x,s(y)) = x + 8y + 8 >= x + 4y + 1 = g(f(x,y),0()) g(s(x),y) = 2x + 4y + 2 >= x + 4y + 1 = g(f(x,y),0()) g(f(x,y),0()) = x + 4y + 1 >= x + 4y + 1 = f(g(x,0()),g(y,0())) problem: DPs: TRS: g(0(),f(x,x)) -> x g(x,s(y)) -> g(f(x,y),0()) g(s(x),y) -> g(f(x,y),0()) g(f(x,y),0()) -> f(g(x,0()),g(y,0())) Qed