#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
vector <int> graph [100005];
int viz[100005];
 
void dfs (int node)
{
    viz[node] = 1;
    int dim = graph[node].size(); //nr vecini nod
    for(int i=0; i<dim; i++)
    {
        int vecin = graph[node][i];
        if(!viz[vecin])
            dfs(vecin);
    }
}
 
int main ()
{
    int n, m, x, y;
    f>>n>>m;
    for(int i=0; i<m; i++)
    {
        f>>x>>y;//muchiile
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    int nr = 0;
    for(int i=1; i<=n; i++)
        if(!viz[i])
        {
            dfs(i);
            nr++;
        }
    g<<nr;
}