func_code_string: #include <bits/stdc++.h>   using namespace std;   void solve() {     int a = 1, l = -1, r = -1;     string s;     for (int i = 1; i <= 30; i++) {       cout <<  ?   << (1 << i) <<     << (1 << (i - 1)) << endl;       cin >> s;       if (s ==  x ) {         continue;       } else {         l = (1 << (i - 1)) + 1;         r = (1 << i);         break;       }     }     if (r == 2) {       cout <<  ! 2  << endl;       return;     } else if (l == -1) {       cout <<  ! 1  << endl;       return;     }     int GUESS1 = r;     l = 0, r = r >> 1;     int md, ans;     while (l < r) {       md = (l + r) >> 1;       cout <<  ?   << GUESS1 <<     << md << endl;       cin >> s;       if (s ==  x ) {         l = md + 1;         ans = md;       } else {         r = md;       }     }     cout <<  !   << GUESS1 - ans << endl;   }   int32_t main() {     string now;     while (cin >> now) {       if (now ==  end ) break;       solve();     }     return 0;   }   