#include <bits/stdc++.h>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int const N=100005;
vector <int> G[N];
int comp[N];
int nr_comp;
void dfs(int node)
{
    if(comp[node])return;
    comp[node]=nr_comp;
    vector<int>::iterator it;
    for(it=G[node].begin();it!=G[node].end();it++)
        dfs(*it);
}
int main()
{
    /*ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);*/
    int n,m;
    fin>>n>>m;
    while(m--)
    {
        int x,y;
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i=1;i<=n;i++)
    {
        if(!comp[i])
        {
            nr_comp++;
dfs(i);
        }

    }
    fout<<nr_comp;

}