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


#define P 1999999973
using namespace std;

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

int viz[100005], n, m, s, d[100005];
vector<int>L[100005];

void Dfs(int nod)
{
    viz[nod] = 1;
    for (auto i : L[nod])
        if (!viz[i])
            Dfs(i);
}

int main()
{
    int x, y, nrc = 0;
    fin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        fin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    for (int i = 1; i <= n; i++)
        if (!viz[i])
        {
            nrc++;
            Dfs(i);
        }
    fout << nrc;
    return 0;
}