#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

const int nlim = 100005;
int n, m;
bool vizitat[nlim];
unsigned int contor = 0;

vector <int> muchii[nlim];

void dfs(int Nod)
{
    vizitat[Nod] = 1;
    for(unsigned int i = 0; i < muchii[Nod].size(); i++)
    {
        int vecin = muchii[Nod][i];
        if(!vizitat[vecin])
            dfs(vecin);
    }
}

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

    }
    for(int i = 1; i <= n; i++)
    {
        if(!vizitat[i])
        {
            contor += 1;
            dfs(i);
        }
    }
}

int main()
{
    citire();
    fout << contor << " " << '\n';

}