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

using namespace std;

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

const int NMAX = 100001;

int viz[NMAX], nr_comp;
vector<int> adj[NMAX];

void DFS(int start, int nr_noduri) {
    viz[start] = nr_comp;
    for (int nod : adj[start]) {
        if (viz[nod] == 0) {
            DFS(nod, nr_noduri);
        }
    }
}

int main() {
    int n, m;
    fin >> n >> m;
    for (int i = 0; i < m; i++) {
        int x, y;
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    fin.close();
    for (int i = 1; i <= n; i++) {
        if (viz[i] == 0) {
            nr_comp++;
            DFS(i, n);
        }
    }
    fout << nr_comp << '\n';
    fout.close();
    return 0;
}