func_code_string: #include <bits/stdc++.h>   int main() {     long n;     scanf( %ld , &n);     std::vector<long> a(n);     for (long p = 0; p < n; p++) {       scanf( %ld , &a[p]);     }     sort(a.begin(), a.end());     long cur(0);     for (long p = 0; p < n; p++) {       if (a[p] >= cur + 1) {         ++cur;       }     }     printf( %ld n , cur);     return 0;   }   