func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long n, m, val, i, j = 0, sum = 0, k = 0;     vector<long> toys;     vector<long> selected;     cin >> n >> m;     for (i = 0; i < n; i++) {       cin >> val;       toys.push_back(val);     }     sort(toys.begin(), toys.end());     for (i = 0; i < 1000000000; i++) {       if (j < (long)toys.size()) {         if (toys[j] == (i + 1)) {           j++;         } else {           if (sum + i + 1 <= m) {             selected.push_back(i + 1);             sum += i + 1;             k++;           } else {             break;           }         }       } else if (sum + i + 1 <= m) {         selected.push_back(i + 1);         sum += i + 1;         k++;       } else {         break;       }     }     cout << k << endl;     for (auto t : selected) {       cout << t <<    ;     }     cout << endl;     return 0;   }   