#include <bits/stdc++.h>
#define nmax 100010
using namespace std;

ofstream g("dfs.out");

vector <int> v[nmax];
int n, m, nc, viz[nmax];

int dfs(int nod)
{
    viz[nod] = 1;
    for(int i = 0; i < v[nod].size(); i ++)
    {
        if(!viz[v[nod][i]])
            dfs(v[nod][i]);
    }

}

void citire()
{
    ifstream f("dfs.in");
    f>>n>>m;
    for(int i = 1; i <= m; i++)
    {
        int x, y;
        f>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    f.close();
}

int main()
{

    citire();
    for(int i = 1; i <= n; i++ )
        if(!viz[i])
        {
            nc++;
            dfs(i);
        }
    g<<nc;
    return 0;
}