#include <bits/stdc++.h>   int du[100010], fa[100010], s1[100010], s2[100010];   int find(int x) {     if (x != fa[x]) fa[x] = find(fa[x]);     return fa[x];   }   int main() {     int n, m, x, y, i, j, k, sum;     scanf( %d%d , &n, &m);     for (i = 1; i <= n; i++) fa[i] = i;     memset(du, 0, sizeof(du));     memset(s1, 0, sizeof(s1));     memset(s2, 0, sizeof(s2));     for (i = 1; i <= m; i++) {       scanf( %d%d , &x, &y);       j = find(x);       k = find(y);       du[x]++;       du[y]++;       if (j != k) {         if (j < k)           fa[k] = j;         else           fa[j] = k;       }     }     for (i = 1; i <= n; i++) {       j = find(i);       s1[j] = s1[j] + du[i];       s2[j]++;     }     sum = 0;     for (i = 1; i <= n; i++)       if (s2[i] != 0) {         j = s1[i] / 2;         if (j < s2[i]) sum = sum + s2[i] - j;       }     printf( %d n , sum);   }   