#include <bits/stdc++.h>
//#include <atcoder/modint>

using namespace std;
//using namespace atcoder;
using ll = long long;
//using mint = modint998244353;

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    int p=1;
    vector<int> v;
    v.push_back(p);
    for (int i=1; i<30; i++){
        p *= 2;
        v.push_back(p);
    }
    for (auto z : views::reverse(v)){
        cout << z << endl;
        cin >> p;
        if (p == 1) return 0;
    }

    return 0;
}