#include <bits/stdc++.h>
#define nmax 100001
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n,m;
vector<int>h[nmax];
int viz[nmax];
void Citire()
{
    int i,x,y;
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        h[x].push_back(y);
        h[y].push_back(x);
    }
}
void DFS(int varf)
{
    int i;
    viz[varf]=1;
    for(i=0;i<h[varf].size();i++)
        if(!viz[h[varf][i]])
    {
        viz[h[varf][i]]=1;
        DFS(h[varf][i]);
    }
}
void Componente()
{
    int i,sol=0;
    for(i=1;i<=n;i++)
        if(!viz[i])
    {
        sol++;
        DFS(i);
    }
    fout<<sol<<" ";
}
int main()
{
    Citire();
    Componente();
    fin.close();
    fout.close();
    return 0;
}