func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename S, typename T>   ostream& operator<<(ostream& out, pair<S, T> const& p) {     out <<  (  << p.first <<  ,   << p.second <<  ) ;     return out;   }   template <typename T>   ostream& operator<<(ostream& out, vector<T> const& v) {     long long l = v.size();     for (long long i = 0; i < l - 1; i++) out << v[i] <<    ;     if (l > 0) out << v[l - 1];     return out;   }   template <typename T>   void trace(const char* name, T&& arg1) {     cout << name <<   :   << arg1 <<   n ;   }   template <typename T, typename... Args>   void trace(const char* names, T&& arg1, Args&&... args) {     const char* comma = strchr(names + 1,  , );     cout.write(names, comma - names) <<   :   << arg1 <<   |  ;     trace(comma + 1, args...);   }   int n, m;   int a[200], b[200];   vector<int> ans;   bool check(int no) {     for (int i = 0; i < n; i++) {       if (a[i] <= no and b[i] >= no) {         return true;       }     }     return false;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     cin >> n >> m;     for (int i = 0; i < n; i++) {       cin >> a[i] >> b[i];     }     int c = 0;     for (int i = 1; i <= m; i++) {       if (check(i) == false) {         c++;         ans.push_back(i);       }     }     cout << c <<   n ;     cout << ans;   }   