YES Problem: b(x,y) -> c(a(c(y),a(0(),x))) a(y,x) -> y a(y,c(b(a(0(),x),0()))) -> b(a(c(b(0(),y)),x),0()) Proof: DP Processor: DPs: b#(x,y) -> a#(0(),x) b#(x,y) -> a#(c(y),a(0(),x)) a#(y,c(b(a(0(),x),0()))) -> b#(0(),y) a#(y,c(b(a(0(),x),0()))) -> a#(c(b(0(),y)),x) a#(y,c(b(a(0(),x),0()))) -> b#(a(c(b(0(),y)),x),0()) TRS: b(x,y) -> c(a(c(y),a(0(),x))) a(y,x) -> y a(y,c(b(a(0(),x),0()))) -> b(a(c(b(0(),y)),x),0()) Matrix Interpretation Processor: dim=2 usable rules: b(x,y) -> c(a(c(y),a(0(),x))) a(y,x) -> y a(y,c(b(a(0(),x),0()))) -> b(a(c(b(0(),y)),x),0()) interpretation: [a#](x0, x1) = [0 2]x0 + [2 0]x1, [b#](x0, x1) = [2 0]x0 + [0 2]x1 + [3], [2 1] [1 0] [a](x0, x1) = [0 2]x0 + [2 0]x1, [0] [0] = [1], [0 1] [c](x0) = [0 0]x0, [3 0] [0 1] [2] [b](x0, x1) = [3 0]x0 + [0 0]x1 + [0] orientation: b#(x,y) = [2 0]x + [0 2]y + [3] >= [2 0]x + [2] = a#(0(),x) b#(x,y) = [2 0]x + [0 2]y + [3] >= [2 0]x + [2] = a#(c(y),a(0(),x)) a#(y,c(b(a(0(),x),0()))) = [6 0]x + [0 2]y + [6] >= [0 2]y + [3] = b#(0(),y) a#(y,c(b(a(0(),x),0()))) = [6 0]x + [0 2]y + [6] >= [2 0]x = a#(c(b(0(),y)),x) a#(y,c(b(a(0(),x),0()))) = [6 0]x + [0 2]y + [6] >= [2 0]x + [5] = b#(a(c(b(0(),y)),x),0()) [3 0] [0 1] [2] [2 0] [2] b(x,y) = [3 0]x + [0 0]y + [0] >= [0 0]x + [0] = c(a(c(y),a(0(),x))) [1 0] [2 1] a(y,x) = [2 0]x + [0 2]y >= y = y [3 0] [2 1] [3] [3 0] [3] a(y,c(b(a(0(),x),0()))) = [6 0]x + [0 2]y + [6] >= [3 0]x + [0] = b(a(c(b(0(),y)),x),0()) problem: DPs: TRS: b(x,y) -> c(a(c(y),a(0(),x))) a(y,x) -> y a(y,c(b(a(0(),x),0()))) -> b(a(c(b(0(),y)),x),0()) Qed