#include <bits/stdc++.h>
using namespace std;
ifstream cin("dfs.in");
ofstream cout("dfs.out");
int n,m,i,k;
vector <int> v[100000];
bool viz[100000];
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() {
    cin >> n;
    cin >> m;
    for (i=1; i<=m; i++){
        int a,b;
        cin >> a;
        cin >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for (i=1; i<=n; i++){
        if (!viz[i]){
            dfs(i);
            k++;
        }
    }
    cout << k;
}