#include<fstream>
#include<vector>
using namespace std;
ifstream in("dfs.in");
ofstream out("dfs.out");
vector <int> g[100002];
bool viz[100002];
void dfs(int nod)
{
    viz[nod]=1;
    for(int j=0;j<g[nod].size();j++)
    {
        if(viz[g[nod][j]]==0)
        {
            dfs(g[nod][j]);
        }
    }
}
int main()
{
    int i,n,m,x,y,nrc=0;
    in>>n>>m;
    while(m--)
    {
        in>>x>>y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    for(i=1;i<=n;i++)
    {
          if(viz[i]==0)
          {
              dfs(i);
              nrc++;
          }
    }
    out<<nrc;
    in.close();
    out.close();
    return 0;
}