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)) Usable Rule 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(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)) Arctic Interpretation Processor: dimension: 1 usable rules: 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)) interpretation: [c#](x0, x1, x2) = 0, [f#](x0) = x0, [f](x0) = 3x0 + 3, [b](x0, x1) = x0 + 1x1 + 0, [c](x0, x1, x2) = 2x1 + x2, [a] = 0 orientation: f#(c(c(a(),y,a()),b(x,z),a())) = 2x + 3z + 2 >= 0 = f#(a()) f#(c(c(a(),y,a()),b(x,z),a())) = 2x + 3z + 2 >= 0 = c#(f(a()),z,z) f#(c(c(a(),y,a()),b(x,z),a())) = 2x + 3z + 2 >= 2z = f#(c(f(a()),z,z)) f#(b(b(x,f(y)),z)) = x + 4y + 1z + 4 >= 0 = f#(a()) f#(b(b(x,f(y)),z)) = x + 4y + 1z + 4 >= 1y + 3 = f#(b(b(f(a()),y),y)) f#(b(b(x,f(y)),z)) = x + 4y + 1z + 4 >= 0 = c#(z,x,f(b(b(f(a()),y),y))) f(b(b(x,f(y)),z)) = 3x + 7y + 4z + 7 >= 2x + 4y + 6 = c(z,x,f(b(b(f(a()),y),y))) c(b(a(),a()),b(y,z),x) = x + 2y + 3z + 2 >= 2z + 1 = b(a(),b(z,z)) problem: DPs: TRS: 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