/*
https://www.infoarena.ro/problema/dfs
*/
#include<iostream>
#include<vector>
#include<fstream>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
int n,m,i,x,y;
vector<vector<int>> a;
vector<int> viz;
void dfs(int nod)
{
    viz[nod]=1;
    for(auto it:a[nod])
        if(viz[it]==0)
            dfs(it);
}
int main()
{

    f>>n>>m;
    a.resize(n+1);
    viz.resize(n+1,0);
    for(i=1;i<=m;i++)
    {
        f>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    int contor=0;
    for(i=1;i<=n;i++)
        if(viz[i]==0)
        {
            contor++;
            dfs(i);
        }
    g<<contor;
    return 0;
}