#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

vector <vector <int> > v(100001);
vector <bool> viz(100001, false);

int dfs(int nod) {
    viz[nod] = true;

    for (auto vecin : v[nod])
        if (!viz[vecin])
            dfs(vecin);
}

int main() {
    int n, m;
    int a, b;

    in >> n >> m;
    for (int i = 0; i < m; i++) {
        in >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }

    int comp = 0;
    for (int i = 1; i < n + 1; i++) {
        if (!viz[i]) {
            dfs(i);
            comp++;
        }
    }

    out << comp;

    return 0;
}