#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
typedef unsigned long long ul;
typedef long long ll;
using namespace std;

ll n, m, a, b, num;
vector <ll> g[100010];
bool viz[100010];

void dfs(ll nod)
{
    viz[nod] = 1;
    for (auto i : g[nod])
    {
        if(!viz[i])
            dfs(i);
    }
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(); cout.tie();
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");

    cin >> n >> m;
    for (ll i = 0; i < m; i++)
    {
        cin >> a >> b;
        g[a].pb(b);
        g[b].pb(a);
    }

    num = 0;
    for (ll i = 1; i <= n; i++)
    {
        if (!viz[i])
        {
            dfs(i);
            num++;
        }
    }
    cout << num;

    return 0;
}