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

ifstream fin("dfs.in");
ofstream fout("dfs.out");

vector<int> L[100005];
int vis[100005];

void dfs( int node)
{
     vis[node] = 1;
     for ( auto vec : L[node])
     {
          if ( vis[vec] == 0)
          {
               dfs(vec);
          }
     }
}

int main()
{
     int n , m ;
     fin>>n>>m;
     for ( int i = 1; i <=m ; i++)
     {
          int x, y;
          fin>>x>>y;
          L[x].push_back(y);
          L[y].push_back(x);
     }

     int cc = 0;
     for ( int i = 1; i <=n; i++)
     {
          if ( vis[i] == 0)
          {
               cc++;
               dfs(i);
          }
     }

     fout<<cc;
}