#include <bits/stdc++.h>
using namespace std;
using ll = long long;
bool chmin(auto &a, const auto &b) {
    if (a <= b) return 0;
    a = b;
    return 1;
}
bool chmax(auto &a, const auto &b) {
    if (a >= b) return 0;
    a = b;
    return 1;
}
void solve();
int main() {
    cin.tie(0)->sync_with_stdio(0);
    cout << fixed << setprecision(20);
    ll t = 1;
    // cin >> t;
    for (int i = 1; i <= t; i++) solve();
    return 0;
}
// ll dy[8] = {1, 1, 0, -1, -1, -1, 0, 1}, dx[8] = {0, 1, 1, 1, 0, -1, -1, -1};
ll dy[] = {0, 1, 0, -1}, dx[] = {1, 0, -1, 0};
void solve() {
    ll val = 5e8;
    while (true) {
        cout << val << endl;
        ll r;
        cin >> r;
        if (r != 0) break;
        if (val % 2)
            val = (val + 1) / 2;
        else
            val /= 2;
    }
}