#include <bits/stdc++.h>

using namespace std;
vector <int> v[100001];
bool app[100001];
void dfs(int nod)
{
    app[nod] = 1;
    for (auto x: v[nod])
    {
        if(!app[x])
        {
            dfs(x);
        }
    }
}
int main()
{
    ifstream cin("dfs.in");
    ofstream cout ("dfs.out");
    int n, m;
    cin >> n >> m;
    for( int i = 1; i <= m; i++ )
    {
        int a, b;
        cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    int cnt = 0;
    for(int i = 1; i <= n; i++)
    {
        if (app[i] == 0)
        {
            dfs(i);
            cnt++;
        }
    }
    cout <<cnt;
    return 0;
}