#include <bits/stdc++.h>

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int limita = 100005;
vector < int > v[limita];
bool viz[limita];

int n,x,y,i,nr,m;

void dfs(int nod)
{
    int i,urmator;
    viz[nod]=true;
    for (i=0; i<v[nod].size(); i++)
    {
        urmator=v[nod][i];
        if (!viz[urmator]) dfs(urmator);
    }
}

int main()
{
    fin>>n>>m;
    for (i=1; i<=m; i++)
    {
        fin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }

    for (i=1; i<=n; i++)
    {
        if (!viz[i])
        {
            nr++;
            dfs(i);
        }
    }
    fout<<nr;
    return 0;
}