extern "C" int Seniorious(int); extern "C" int Chtholly(int n, int OvO) { int ans = 1; int l = 1, r = n; int mid = l + r >> 1; while (l <= r) { if (Seniorious(mid) >= 0) { ans = mid; r = mid - 1; } else { l = mid + 1; } mid = l + r >> 1; } return ans; }