#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>
#define NMAX 100005
using namespace std;
vector <int> g[NMAX];
int i, n, m, u, v, p=0;
bool viz[NMAX];
void DFS(int nod)
{
    viz[nod]=1;
    for(int i=0; i<g[nod].size(); i++)
        if(!viz[g[nod][i]])
        {
            viz[g[nod][i]]=1;
            DFS(g[nod][i]);
        }
}
int main()
{
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");
    cin>>n>>m;
    for(i=1; i<=m; i++)
    {
        cin>>u>>v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    for(i=1; i<=n; i++)
        if(!viz[i])
        {
            p++;
            DFS(i);
        }

    cout<<p<<'\n';
    return 0;
}