#include <bits/stdc++.h>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

vector<int> g[100005];

bool viz[100005];

void dfs(int nod)
{
    viz[nod] = true;

    for(int x : g[nod])
        if(viz[x] == false) dfs(x);
}

int main()
{
    int n, m;

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

    int nr = 0;

    for(int i=1;i<=n;i++)
        if(viz[i] == false)
    {
        dfs(i);
        nr ++;
    }

    fout << nr;
}