#include <bits/stdc++.h>

using namespace std;

vector<int> adj[100005];
int save[100005];

int dfs(int nod)
{
    save[nod] = 1;
    for(auto x : adj[nod])
        if(save[x] == 0)
            dfs(x);
}

int main()
{
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");
    int n, m, a, b, cnt = 0;
    cin>>n>>m;
    for(int i=0; i<m; i++)
    {
        cin>>a>>b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }

    for(int i=1; i<=n; i++)
        if(save[i] == 0)
            cnt++, dfs(i);

    cout<<cnt;

    return 0;
}