#include <iostream>
#include <cstdio>
#include <vector>
#define NMAX 100002
using namespace std;

vector<int> adj[NMAX];
bool viz[NMAX];

void dfs(int nod)
{
    viz[nod]=true;
    for(vector<int>::iterator it=adj[nod].begin();it!=adj[nod].end();it++)
        if(!viz[*it])
            dfs(*it);
}

int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    int n,m,x,y,comp_conexe=0;
    cin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        cin>>x>>y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    for(int i=1;i<=n;i++)
        if(!viz[i])
        {
            dfs(i);
            comp_conexe++;
        }
    cout<<comp_conexe;
    return 0;

}