//
// Created by Radu Buzas on 14.10.2022.
//

#include <fstream>
#include <vector>
using namespace std;

ifstream in("dfs.in");
ofstream out("dfs.out");

vector<int> v[100001];
int n, m, cnt;
bool viz[100001];

void dfs(int start){
    viz[start] = true;
    for (auto i: v[start])
        if (!viz[i])
            dfs(i);
}

int main()
{
    int x, y;
    in >> n >> m;
    while(m--){
        in >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
//    for(int i=1;i<=n; ++i)
//        sort(v[i].begin(), v[i].end());
    for (int i = 1; i <= n; ++i)
        if(!viz[i]) {
            dfs(i);
            ++cnt;
        }

    out << cnt;

    return 0;
}