#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int NMAX = 100001;

vector<int> lista[NMAX];
vector<bool> viz(NMAX, false);
int n, m;

void citire()
{
    fin >> n >> m;
    for(int i = 1 ; i <= m ; i++)
    {
        int a,b;
        fin >> a >> b;
        lista[a].push_back(b);
        lista[b].push_back(a);
    }
}

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


int main()
{
    citire();
    int nrcomp = 0;
    for(int i = 1 ; i <= n ; i++)
        if(viz[i] == 0)
        {
            nrcomp++;
            dfs(i);
        }
    fout << nrcomp;
}