func_code_string: #include <bits/stdc++.h>   using namespace std;   const int maxn = 2e5 + 5;   int n, m;   int pre[maxn];   void init(int n) {     for (int i = 0; i <= n + 1; i++) pre[i] = i;   }   int finds(int x) {     if (x == pre[x])       return x;     else       return pre[x] = finds(pre[x]);   }   int main() {     while (cin >> n >> m) {       int ans = 0;       init(n);       for (int i = 1, a, b; i <= m; i++) {         cin >> a >> b;         int fa = finds(a);         int fb = finds(b);         if (fa != fb) {           pre[fa] = fb;         } else           ans++;       }       cout << ans << endl;     }     return 0;   }   