#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

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

const int NMax = 100001;
vector<int> v[NMax];
bool vizitat[NMax] = {false};

void DFS(int nod)
{
    vizitat[nod] = true;

    for (unsigned int i = 0; i < v[nod].size(); ++i)
    {
        int Next = v[nod][i];
        if(!vizitat[Next])
            DFS(Next);
    }
}

int main()
{
    int n, m;
    int x, y;
    fin >> n >> m;

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

    int componente_conexe = 0;
    for (int i = 1; i <= n; ++i)
    {
        if(!vizitat[i])
        {
            componente_conexe++;
            DFS(i);
        }
    }

    fout << componente_conexe;
}