YES(?,O(n^2)) Problem: add(0(),x) -> x add(s(x),y) -> s(add(x,y)) Proof: Matrix Interpretation Processor: dimension: 2 interpretation: [2] [s](x0) = x0 + [1], [1 6] [8] [add](x0, x1) = [0 1]x0 + x1 + [0], [8] [0] = [0] orientation: [16] add(0(),x) = x + [0 ] >= x = x [1 6] [16] [1 6] [10] add(s(x),y) = [0 1]x + y + [1 ] >= [0 1]x + y + [1 ] = s(add(x,y)) problem: Qed