#include <bits/stdc++.h>
 
 using namespace std;

int n, m, viz[100001], ans;

vector<int>adj[100001];

 void dfs (int nod)
 {
     viz[nod] = 1;
     for (int i = 0; i < adj[nod].size(); i++)
      {
          if (viz[adj[nod][i]] == 0)
          {
              dfs(adj[nod][i]);
          }
      }
 }
 
 
int main()
{
    
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);
    
    cin >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        int x, y;
        cin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
   for(int i = 1; i <= n; i++)
   {
       if(viz[i] == 0)
       {
           dfs(i);
           ans++;
       }
   }
   cout << ans;
}