#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<vector <int> > edges;
vector<bool> viz;
void dfs(int nod)
{
    int next;
    viz[nod]=true;
    for(auto next:edges[nod])
    {
        if(!viz[next])
            dfs(next);
    }
}
int main()
{
    int n,m,cnt=0;
    fin>>n>>m;
    viz.resize(n);
    for(int i=1;i<=m;i++)
    {
        int a,b;
        fin>>a>>b;
        edges[a].push_back(b);
        edges[b].push_back(a);
    }
    for(int i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            cnt++;
            dfs(i);
        }
    }
    fout<<cnt;
    return 0;
}