1for (int c0 = 1; c0 <= min(2 * b - 1, n); c0 += 1) 2 for (int c1 = max(-b + 1, -n + 1); c1 <= min(n - c0, b - c0); c1 += 1) 3 for (int c2 = max(1, c0 + c1); c2 <= min(n + c1, n); c2 += 1) 4 s0(-c0 - c1 + c2 + 1, -c1 + c2, c2); 5