func_code_string: #include <bits/stdc++.h>   using namespace std;   int dfs(vector<int>* v, int n) {     int cost = -1;     for (int i = 1; i <= n; i++) {       for (int j = i + 1; j <= n; j++) {         if (binary_search(v[i].begin(), v[i].end(), j) == 0) continue;         for (int k = 0; k < v[i].size(); k++) {           for (int s = 0; s < v[j].size(); s++) {             if (v[i][k] == v[j][s]) {               int p = v[i][k];               int ct = v[i].size() + v[j].size() + v[p].size() - 6;               if (cost == -1) {                 cost = ct;               } else {                 cost = min(cost, ct);               }               break;             }           }         }       }     }     return cost;   }   int main() {     int n, m;     cin >> n >> m;     vector<int> v[n + 1];     for (int i = 0; i < m; i++) {       int x, y;       cin >> x >> y;       v[x].push_back(y);       v[y].push_back(x);     }     for (int i = 1; i < n + 1; i++) {       sort(v[i].begin(), v[i].end());     }     int cost = dfs(v, n);     cout << cost <<   n ;     return 0;   }   