#include <iostream>
#include <vector>
#include <algorithm>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
#define rep(i, n) for (int i = 0; i< (int)(n); i++) 

int main(){
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    ll ans = 1e9;
    rep(i, 30){
        cout << ans << endl;
        int r; cin >> r;
        if(r == -1){
            return 0;
        }else if(r == 0){
            ans /= 2;
        }
    }

    return 0;
}