func_code_string: #include <bits/stdc++.h>   using namespace std;   using namespace std;   bool debug = 1;   int main() {     int n, m;     scanf( %d %d , &n, &m);     int amn[n + 1];     vector<vector<int> > v;     v.resize(n + 1);     for (int i = 0; i < m; i++) {       int a, b;       scanf( %d %d , &a, &b);       v[a].push_back(b);       v[b].push_back(a);       amn[a]++;       amn[b]++;     }     bool fs[n + 1];     fill(fs, fs + n + 1, 0);     if (0)       for (int i = 1; i <= n; i++)         if (v[i].size() == 1) fs[i] = 1;     int k = 0;     bool is;     do {       bool nfs[n + 1];       for (int i = 1; i <= n; i++) nfs[i] = fs[i];       is = 0;       k++;       for (int i = 1; i <= n; i++) {         if (fs[i]) continue;         int amnoth = 0;         for (int j = 0; j < v[i].size(); j++) {           int oth = v[i][j];           if (!fs[oth]) amnoth++;         }         if (amnoth == 1) {           nfs[i] = 1;           is = 1;         }       }       for (int i = 1; i <= n; i++) fs[i] = nfs[i];     } while (is);     printf( %d n , k - 1);     return 0;   }   