#include <bits/stdc++.h>

using namespace std;

int n,m,i,nr;
vector <int> v[100005];
bool viz[100005];

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

int main() 
{
	ifstream cin("dfs.in")
	ofstream cout("dfs.out");
    cin>>n>>m;
    for (i=1; i<=m; i++)
    {
        int a,b;
        cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    
    for (i=1; i<=n; i++)
    {
        if (!viz[i])
        {
            dfs(i);
            nr++;
        }
    }
    cout<<nr;
}