#include using namespace std; int main() { int N; cin >> N; int L = 1, R = N + 1; //[L, R) for (int i = 0; i < 10; i++) { int mid = (L + R) / 2; cout << "? " << mid << endl; int res; cin >> res; if (res < mid) { R = mid; } else { L = mid; } } if (L == N) { cout << "No" << endl; } else { cout << "Yes " << L << ' ' << R << endl; } }