#include <fstream>
#include <vector>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
void DFS(int nod, vector<int> &Viz, vector<vector<int>> &Graf)
{
    Viz[nod]=1;
    for (auto i:Graf[nod])
        if (Viz[i]==0)  DFS(i,Viz,Graf);
}
int main()
{
    int nod, muchii, nr_comp=0;
    f>>nod>>muchii;

    vector < vector <int> > Graf(nod+1);
    vector <int> Viz(nod+1,0);

    for (int i=1;i<=muchii;i++)
    {
        int x,y;
        f>>x>>y;
        Graf[x].push_back(y);
        Graf[y].push_back(x);
    }
    for (int i=1;i<=nod;i++)
    {
        if (Viz[i]==0)
        {
            nr_comp++;
            DFS(i,Viz,Graf);
        }
    }
    g<<nr_comp;
    return 0;
}