#include <bits/stdc++.h>
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n, m, i, x, y, cnt_comp;
vector<vector<int>> adj;
vector<int> viz;

void DFS(int nod)
{
    viz[nod]=1;
    for(int i : adj[nod])
        if (!viz[i])
        DFS(i);
}
int main()
{
    fin >> n >> m;
    adj.resize(n+5);
    viz.resize(n+5);
    for (i=1;i<=m;i++)
    {
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    for (i=1;i<=n;i++)
        if (!viz[i])
        {
            cnt_comp++;
            DFS(i);
        }

    fout << cnt_comp << "\n";
    return 0;
}