#include <iostream>
#include <vector>
#include <fstream>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int N = 100.001;
int n;

vector <int> a[N];
bool viz[N];
void dfs (int x)
{
    int i,y;
    viz[x]=true;
    for(i=0 ; i<a[x].size() ; i++)
    {
        y=a[x][i];
        if (!viz[y])
            dfs (y);
    }
}


int main()
{
    int m , x , y , i;
    fin>>n>>m;

    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        ///Se adauga y in lista lui x;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    int nr=0;
    for(i=1;i<=n;i++)
        if(!viz[i])
        {
            dfs(i);
            nr++;
        }

    fout<<nr;
    return 0;
}