func_code_string: #include <bits/stdc++.h>   using namespace std;   int ask(int i, int j) {     cout <<  ?   << i <<     << j << endl;     fflush(stdout);     int val;     cin >> val;     return val;   }   int main() {     int n;     cin >> n;     int a[n + 1];     int index = 1, i, x, y;     for (int i = 2; i <= n; i++) {       x = ask(index, i);       y = ask(i, index);       if (x > y) {         a[index] = x;         index = i;       } else if (y > x) {         a[i] = y;       }     }     a[index] = n;     cout <<  !  ;     for (i = 1; i <= n; i++) cout << a[i] <<    ;     cout <<   n ;     fflush(stdout);     return 0;   }   