func_code_string: #include <bits/stdc++.h>   using namespace std;   char rep;   void query(long long x, long long y) {     cout <<  ?   << x <<     << y << endl;     cin >> rep;     return;   }   void solve() {     long long x = 0;     long long y = 1;     while (true) {       query(x, y);       if (rep ==  x ) {         break;       }       x = y;       y = y * 2;     }     long long l = x + 1;     long long r = y;     while (l != r) {       long long med = (l + r) / 2;       query(med, y);       if (rep ==  x ) {         l = med + 1;       } else {         r = med;       }     }     cout <<  !   << l << endl;     return;   }   int main() {     string s;     while (true) {       cin >> s;       if (s[0] ==  s ) {         solve();       } else {         break;       }     }     return 0;   }   