func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m;     cin >> n >> m;     map<pair<int, int>, int> mp;     map<int, int> mp1;     vector<pair<int, int>> v;     for (int i = 0; i < m; i++) {       int x, y;       cin >> x >> y;       mp1[x]++;       mp1[y]++;       mp[{x, y}]++;       mp[{y, x}]++;     }     bool f = 0;     for (int i = 1; i <= n; i++) {       v.push_back({mp1[i], i});     }     sort(v.begin(), v.end());     for (int i = 0; i < v.size(); i++) {       if (f) break;       for (int j = i - 1; j > -1 && v[i].first + v[j].first >= m; j--) {         int x = v[i].second, y = v[j].second;         int ans = 0;         ans += mp1[x];         ans += mp1[y];         ans -= mp[{x, y}];         if (ans >= m) {           f = 1;           break;         }       }     }     if (f)       cout <<  YES ;     else       cout <<  NO ;     return 0;   }   