#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

int viz[100002],n,m;
vector <int> a[100002];

void DFS(int nod)
{
    int i,j;
    viz[nod]=1;
        for(j=0;j<a[nod].size();++j)
            if(viz[a[nod][j]]==0)
                DFS(a[nod][j]);
}

int main()
{
    int i,x,y,k=0;

    fin>>n>>m;

    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    for(i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            DFS(i);
            k++;
        }
    }
    fout<<k;

}