/** Sa se determine numarul componentelor conexe ale grafului.
*/
#include<iostream>
#include<cmath>
#include<cstring>
#include<fstream>
#include<vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int> G[100005];
int x,y;
bool viz[100005];
int k;
void citire(int m)
{
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
}

void DFS(int nod)
{
    viz[nod]=true;
    for(int i=0;i<G[nod].size();i++)
        if(!viz[G[nod][i]])
        {
            DFS(G[nod][i]);

        }

}
int main()
{
    int n,m;
    fin>>n>>m;
    citire(m);
    for(int i=1;i<=n;i++)
        if(!viz[i])
        {
                k++;
                DFS(i);
        }
    fout<<k;

}