#include <bits/stdc++.h>
#define nmax 100001

using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

vector <int > matrice[nmax];
bool viz[nmax];
int nc;

void dfs(int nod)
{
    viz[nod]=true;
    for(int i=0;i< matrice[nod].size();i++){
        if(viz[matrice[nod][i]]==0)
            dfs(matrice[nod][i]);
    }
}

int main()
{
    int n,m;
    int x,y;
    f>>n>>m;
    for(int i=1;i<=m;i++)
    {
        f>>x>>y;
        matrice[x].push_back(y);
        matrice[y].push_back(x);
    }

    for(int i=1;i<=n;i++)
        if(viz[i]==0){
            dfs(i);
            nc++;
        }

    g<<nc;
    return 0;
}