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

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

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

void DFS(int k)
{
    v[k] = 1;
    for (int i : L[k])
        if (v[i] == 0)  
            DFS(i);
}

int main()
{
    int i, j, nrC;
    fin >> n >> m;
    while (m--)
    {
        fin >> i >> j;
        L[i].push_back(j);
        L[j].push_back(i);
    }

    nrC = 0;
    for (i = 1; i <= n; i++)
        if (v[i] == 0)
        {
            nrC++;
            DFS(i);
        }
    fout << nrC << "\n";
    return 0;
}