#include <fstream>
#include <vector>
#define LGMAX 100001
using namespace std;

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

vector <int> G[LGMAX];
bool uz[LGMAX];
int n, m, componenteConexe;

void citire();
void rezolvare();
void DFS(int nod);

int main()
{
    citire();
    rezolvare();
    return 0;
}
void citire()
{
    int x, y;
    fin >> n >> m;
    for (int i=0; i<m ;i++)
    {
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
}
void rezolvare()
{
    for (int i=1; i<=n; i++)
        {
        if (!uz[i])
        {
            componenteConexe++;
            DFS(i);
        }
        }
    fout << componenteConexe << '\n';
}
void DFS(int nod)
{
    uz[nod] = 1;
    for (unsigned int i=0; i<G[nod].size(); i++)
    {
        if (!uz[G[nod][i]])
        {
            DFS(G[nod][i]);
        }
    }
}