#include <bits/stdc++.h>

using namespace std;

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

void dfs(int nod){
    viz[nod]=1;
    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++)
    {
        cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    
    for (int i=1; i<=n; i++)
        if (!viz[i]) dfs(i),nr++;
        
    cout<<nr;
}