#include<iostream>
#include<fstream>
#include<vector>
#define nmax 100010
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n,m,viz[nmax],nr=0;
vector<int>G[nmax];
void dfs(int nod)
{
    viz[nod]=1;
    for(auto it: G[nod])
    {
        if(!viz[it])
        {
            dfs(it);
        }
    }
}
int main()
{
    int x,y,i;
    cin>>n>>m;
    while(m--)
    {
        cin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(i=1;i<=n;i++)
    {
        if(!viz[i])
        {
            nr++;
            dfs(i);
        }
    }
    cout<<nr;
   
    return 0;
}