YES(?,O(n^1)) Problem: f(x,x) -> a() f(g(x),y) -> f(x,y) Proof: RT Transformation Processor: strict: f(x,x) -> a() f(g(x),y) -> f(x,y) weak: Matrix Interpretation Processor: dimension: 1 interpretation: [g](x0) = x0 + 2, [a] = 0, [f](x0, x1) = x0 + x1 orientation: f(x,x) = 2x >= 0 = a() f(g(x),y) = x + y + 2 >= x + y = f(x,y) problem: strict: f(x,x) -> a() weak: f(g(x),y) -> f(x,y) Matrix Interpretation Processor: dimension: 1 interpretation: [g](x0) = x0, [a] = 0, [f](x0, x1) = x0 + x1 + 1 orientation: f(x,x) = 2x + 1 >= 0 = a() f(g(x),y) = x + y + 1 >= x + y + 1 = f(x,y) problem: strict: weak: f(x,x) -> a() f(g(x),y) -> f(x,y) Qed