YES(?,O(n^2)) Problem: f(f(X)) -> f(g(f(g(f(X))))) f(g(f(X))) -> f(g(X)) Proof: Complexity Transformation Processor: strict: f(f(X)) -> f(g(f(g(f(X))))) f(g(f(X))) -> f(g(X)) weak: Matrix Interpretation Processor: dimension: 1 max_matrix: 1 interpretation: [g](x0) = x0, [f](x0) = x0 + 1 orientation: f(f(X)) = X + 2 >= X + 3 = f(g(f(g(f(X))))) f(g(f(X))) = X + 2 >= X + 1 = f(g(X)) problem: strict: f(f(X)) -> f(g(f(g(f(X))))) weak: f(g(f(X))) -> f(g(X)) Matrix Interpretation Processor: dimension: 2 max_matrix: [1 1] [0 0] interpretation: [1 0] [g](x0) = [0 0]x0, [1 1] [0] [f](x0) = [0 0]x0 + [1] orientation: [1 1] [1] [1 1] [0] f(f(X)) = [0 0]X + [1] >= [0 0]X + [1] = f(g(f(g(f(X))))) [1 1] [0] [1 0] [0] f(g(f(X))) = [0 0]X + [1] >= [0 0]X + [1] = f(g(X)) problem: strict: weak: f(f(X)) -> f(g(f(g(f(X))))) f(g(f(X))) -> f(g(X)) Qed