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

using namespace std;

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

int n, m;
vector<int> v[100005];
bool viz[100005];

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

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

    }
}

int main()
{
    fin >> n >> m;

    for (int i = 0; i < m; i++)
    {
        int x, y;
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }

    int comp = 0;

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

    fout << comp << "\n";

    fin.close();
    fout.close();
    
    return 0;
}