YES Problem: f(a,empty()) -> g(a,empty()) f(a,cons(x,k)) -> f(cons(x,a),k) g(empty(),d) -> d g(cons(x,k),d) -> g(k,cons(x,d)) Proof: Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [1 1 0] [0] [f](x0, x1) = [1 0 0]x0 + [1 0 1]x1 + [0] [0 0 0] [0 0 0] [1], [1 0 0] [1] [cons](x0, x1) = [0 0 0]x0 + x1 + [0] [0 0 0] [0], [0] [empty] = [1] [1], [1 0 0] [g](x0, x1) = [0 0 0]x0 + x1 [0 0 0] orientation: [1 0 0] [1] [1 0 0] [0] f(a,empty()) = [1 0 0]a + [1] >= [0 0 0]a + [1] = g(a,empty()) [0 0 0] [1] [0 0 0] [1] [1 0 0] [1 1 0] [1 0 0] [1] [1 0 0] [1 1 0] [1 0 0] [1] f(a,cons(x,k)) = [1 0 0]a + [1 0 1]k + [1 0 0]x + [1] >= [1 0 0]a + [1 0 1]k + [1 0 0]x + [1] = f(cons(x,a),k) [0 0 0] [0 0 0] [0 0 0] [1] [0 0 0] [0 0 0] [0 0 0] [1] g(empty(),d) = d >= d = d [1 0 0] [1 0 0] [1] [1 0 0] [1 0 0] [1] g(cons(x,k),d) = d + [0 0 0]k + [0 0 0]x + [0] >= d + [0 0 0]k + [0 0 0]x + [0] = g(k,cons(x,d)) [0 0 0] [0 0 0] [0] [0 0 0] [0 0 0] [0] problem: f(a,cons(x,k)) -> f(cons(x,a),k) g(empty(),d) -> d g(cons(x,k),d) -> g(k,cons(x,d)) Matrix Interpretation Processor: dim=1 interpretation: [f](x0, x1) = 2x0 + 2x1, [cons](x0, x1) = 4x0 + x1, [empty] = 1, [g](x0, x1) = 6x0 + 4x1 + 3 orientation: f(a,cons(x,k)) = 2a + 2k + 8x >= 2a + 2k + 8x = f(cons(x,a),k) g(empty(),d) = 4d + 9 >= d = d g(cons(x,k),d) = 4d + 6k + 24x + 3 >= 4d + 6k + 16x + 3 = g(k,cons(x,d)) problem: f(a,cons(x,k)) -> f(cons(x,a),k) g(cons(x,k),d) -> g(k,cons(x,d)) Matrix Interpretation Processor: dim=1 interpretation: [f](x0, x1) = x0 + x1, [cons](x0, x1) = x0 + x1 + 1, [g](x0, x1) = 3x0 + 2x1 + 6 orientation: f(a,cons(x,k)) = a + k + x + 1 >= a + k + x + 1 = f(cons(x,a),k) g(cons(x,k),d) = 2d + 3k + 3x + 9 >= 2d + 3k + 2x + 8 = g(k,cons(x,d)) problem: f(a,cons(x,k)) -> f(cons(x,a),k) Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [1 0 1] [f](x0, x1) = [0 0 0]x0 + [0 0 0]x1 [0 0 0] [0 0 0] , [1 0 0] [1 0 0] [0] [cons](x0, x1) = [0 0 0]x0 + [0 0 0]x1 + [0] [0 0 0] [0 0 1] [1] orientation: [1 0 0] [1 0 1] [1 0 0] [1] [1 0 0] [1 0 1] [1 0 0] f(a,cons(x,k)) = [0 0 0]a + [0 0 0]k + [0 0 0]x + [0] >= [0 0 0]a + [0 0 0]k + [0 0 0]x = f(cons(x,a),k) [0 0 0] [0 0 0] [0 0 0] [0] [0 0 0] [0 0 0] [0 0 0] problem: Qed