#include <iostream>
#include <bits/stdc++.h>
#include <fstream>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
int i,n,nrm,nrc=0;
bool viz[100003];
vector<vector<int>> m;
void citire()
{
    f>>n>>nrm;
    m.resize(n+1);
    for(i=1;i<=nrm;i++)
    {
        int x,y;
        f>>x>>y;
        m[x].push_back(y);
        m[y].push_back(x);
    }
}
void dfs(int nod)
{
    viz[nod]=1;
    for(int i=0;i<m[nod].size();i++)
        if(viz[m[nod][i]]==0)
        {
            dfs(m[nod][i]);
        }
}
int main()
{
    citire();
    for(i=1;i<=n;i++)
        if(viz[i]==0)
        {
            dfs(i);
            nrc++;
        }
    g<<nrc;
}