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

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

#define NMAX 100005

vector<int> v[NMAX];

int viz[NMAX];

void dfs(int nod)
{
    viz[nod] = 1;

    for (auto it : v[nod])
        if (!viz[it])
            dfs(it);
}

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

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

    int nr = 0;

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

    fout << nr;
    return 0;
}