func_code_string: #include <bits/stdc++.h>   int arr[150];   int temp[150];   int main() {     int n, m;     std::cin >> n >> m;     for (int i = 0; i < n; ++i) {       int a, b;       std::cin >> a >> b;       for (int j = a; j <= b; ++j) arr[j]++;     }     int cnt = 0;     for (int i = 1; i <= m; ++i) {       if (!arr[i]) temp[cnt++] = i;     }     std::cout << cnt << std::endl;     for (int i = 0; i < cnt; ++i) {       if (!i)         std::cout << temp[i];       else         std::cout <<     << temp[i];     }     if (cnt) std::cout << std::endl;     return 0;   }   