YES Problem: f(c(c(a(),y,a()),b(x,z),a())) -> b(y,f(c(f(a()),z,z))) f(b(b(x,f(y)),z)) -> c(z,x,f(b(b(f(a()),y),y))) c(b(a(),a()),b(y,z),x) -> b(a(),b(z,z)) Proof: DP Processor: DPs: f#(c(c(a(),y,a()),b(x,z),a())) -> f#(a()) f#(c(c(a(),y,a()),b(x,z),a())) -> c#(f(a()),z,z) f#(c(c(a(),y,a()),b(x,z),a())) -> f#(c(f(a()),z,z)) f#(b(b(x,f(y)),z)) -> f#(a()) f#(b(b(x,f(y)),z)) -> f#(b(b(f(a()),y),y)) f#(b(b(x,f(y)),z)) -> c#(z,x,f(b(b(f(a()),y),y))) TRS: f(c(c(a(),y,a()),b(x,z),a())) -> b(y,f(c(f(a()),z,z))) f(b(b(x,f(y)),z)) -> c(z,x,f(b(b(f(a()),y),y))) c(b(a(),a()),b(y,z),x) -> b(a(),b(z,z)) Matrix Interpretation Processor: dim=1 interpretation: [c#](x0, x1, x2) = 4x0, [f#](x0) = 2x0, [f](x0) = 2x0 + 1, [b](x0, x1) = 2x0 + 3x1 + 1, [c](x0, x1, x2) = x0 + 5x1, [a] = 0 orientation: f#(c(c(a(),y,a()),b(x,z),a())) = 20x + 10y + 30z + 10 >= 0 = f#(a()) f#(c(c(a(),y,a()),b(x,z),a())) = 20x + 10y + 30z + 10 >= 4 = c#(f(a()),z,z) f#(c(c(a(),y,a()),b(x,z),a())) = 20x + 10y + 30z + 10 >= 10z + 2 = f#(c(f(a()),z,z)) f#(b(b(x,f(y)),z)) = 8x + 24y + 6z + 18 >= 0 = f#(a()) f#(b(b(x,f(y)),z)) = 8x + 24y + 6z + 18 >= 18y + 14 = f#(b(b(f(a()),y),y)) f#(b(b(x,f(y)),z)) = 8x + 24y + 6z + 18 >= 4z = c#(z,x,f(b(b(f(a()),y),y))) f(c(c(a(),y,a()),b(x,z),a())) = 20x + 10y + 30z + 11 >= 2y + 30z + 10 = b(y,f(c(f(a()),z,z))) f(b(b(x,f(y)),z)) = 8x + 24y + 6z + 19 >= 5x + z = c(z,x,f(b(b(f(a()),y),y))) c(b(a(),a()),b(y,z),x) = 10y + 15z + 6 >= 15z + 4 = b(a(),b(z,z)) problem: DPs: TRS: f(c(c(a(),y,a()),b(x,z),a())) -> b(y,f(c(f(a()),z,z))) f(b(b(x,f(y)),z)) -> c(z,x,f(b(b(f(a()),y),y))) c(b(a(),a()),b(y,z),x) -> b(a(),b(z,z)) Qed