YES(?,O(n^1)) Problem: a(c(d(x))) -> c(x) u(b(d(d(x)))) -> b(x) v(a(a(x))) -> u(v(x)) v(a(c(x))) -> u(b(d(x))) v(c(x)) -> b(x) w(a(a(x))) -> u(w(x)) w(a(c(x))) -> u(b(d(x))) w(c(x)) -> b(x) Proof: Complexity Transformation Processor: strict: a(c(d(x))) -> c(x) u(b(d(d(x)))) -> b(x) v(a(a(x))) -> u(v(x)) v(a(c(x))) -> u(b(d(x))) v(c(x)) -> b(x) w(a(a(x))) -> u(w(x)) w(a(c(x))) -> u(b(d(x))) w(c(x)) -> b(x) weak: Matrix Interpretation Processor: dimension: 1 max_matrix: 1 interpretation: [w](x0) = x0 + 1, [v](x0) = x0, [u](x0) = x0, [b](x0) = x0, [a](x0) = x0 + 1, [c](x0) = x0 + 1, [d](x0) = x0 orientation: a(c(d(x))) = x + 2 >= x + 1 = c(x) u(b(d(d(x)))) = x >= x = b(x) v(a(a(x))) = x + 2 >= x = u(v(x)) v(a(c(x))) = x + 2 >= x = u(b(d(x))) v(c(x)) = x + 1 >= x = b(x) w(a(a(x))) = x + 3 >= x + 1 = u(w(x)) w(a(c(x))) = x + 3 >= x = u(b(d(x))) w(c(x)) = x + 2 >= x = b(x) problem: strict: u(b(d(d(x)))) -> b(x) weak: a(c(d(x))) -> c(x) v(a(a(x))) -> u(v(x)) v(a(c(x))) -> u(b(d(x))) v(c(x)) -> b(x) w(a(a(x))) -> u(w(x)) w(a(c(x))) -> u(b(d(x))) w(c(x)) -> b(x) Matrix Interpretation Processor: dimension: 1 max_matrix: 1 interpretation: [w](x0) = x0 + 1, [v](x0) = x0 + 1, [u](x0) = x0, [b](x0) = x0, [a](x0) = x0, [c](x0) = x0, [d](x0) = x0 + 1 orientation: u(b(d(d(x)))) = x + 2 >= x = b(x) a(c(d(x))) = x + 1 >= x = c(x) v(a(a(x))) = x + 1 >= x + 1 = u(v(x)) v(a(c(x))) = x + 1 >= x + 1 = u(b(d(x))) v(c(x)) = x + 1 >= x = b(x) w(a(a(x))) = x + 1 >= x + 1 = u(w(x)) w(a(c(x))) = x + 1 >= x + 1 = u(b(d(x))) w(c(x)) = x + 1 >= x = b(x) problem: strict: weak: u(b(d(d(x)))) -> b(x) a(c(d(x))) -> c(x) v(a(a(x))) -> u(v(x)) v(a(c(x))) -> u(b(d(x))) v(c(x)) -> b(x) w(a(a(x))) -> u(w(x)) w(a(c(x))) -> u(b(d(x))) w(c(x)) -> b(x) Qed