func_code_string: #include <bits/stdc++.h>   using namespace std;   mt19937_64 rnd(time(0));   ifstream in;   ofstream out;   const long long INF = LLONG_MAX;   const long double EPS = 1e-9;   const long double pi = 3.141592653589793238462643383279502884;   long long n;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     cout.precision(20);     srand(time(0));     cin >> n;     long long l = 0;     long long r = 1e9;     long long k = 2;     cout <<  0 2  << endl;     cout.flush();     string x;     cin >> x;     if (x[0] ==  b ) swap(l, r);     for (long long i = 0; i < n - 1; i++) {       long long m = (l + r) >> 1;       cout << m <<     << k << endl;       cout.flush();       string x;       cin >> x;       if (x[0] ==  w )         l = m;       else         r = m;     }     cout << l <<     << k - 1 <<     << r <<     << k + 1 << endl;     return 0;   }   