#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned int t = 1000000000;
  while (1) {
  	cout << t << endl;
    int x; cin >> x;
    if (x == 1) {
      return 0;
    }
    else if (x == -1) {
      return 0;
    }
    else t>>=1;
  }
}