func_code_string: #include <bits/stdc++.h>   using namespace std;   const int maxn = 1e6 + 7;   const int inf = INT_MAX;   const long long inff = 1e18;   const int mod = 1e9 + 7;   string s, t;   int32_t main() {     ios::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n;     cin >> n;     cout << 0 <<     << 0 << endl;     cout << flush;     cin >> s;     if (n == 1) {       cout << 0 <<     << 1000000000 <<     << 1000000000 <<     << 0 << endl;       cout << flush;       return 0;     }     cout << 1000000000 <<     << 1000000000 << endl;     cout << flush;     cin >> t;     if (n == 2) {       if (s == t)         cout << 1 <<     << 0 <<     << 1000000000 <<     << 1000000000 - 1              << endl;       else         cout << 0 <<     << 1000000000 <<     << 1000000000 <<     << 0 << endl;       cout << flush;       return 0;     }     if (s != t) {       int l = 1, r = 1000000000 - 1;       for (int i = 1; i <= n - 2; i++) {         int m = (l + r) >> 1;         cout << m <<     << 0 << endl;         cout << flush;         string now;         cin >> now;         if (now == s)           l = m + 1;         else           r = m - 1;       }       cout << 0 <<     << l <<     << l <<     << 0 << endl;       cout << flush;       return 0;     } else {       int l = 1, r = 1000000000 - 1;       for (int i = 1; i <= n - 2; i++) {         int m = (l + r) >> 1;         cout << m <<     << 0 << endl;         cout << flush;         string now;         cin >> now;         if (now == s)           l = m + 1;         else           r = m - 1;       }       cout << l <<     << 0 <<     << 1000000000 <<     << 1000000000 - l << endl;       cout << flush;       return 0;     }   }   