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

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

int n, m;
vector<vector<int>> graf;
vector<int> viz;

void dfs(int nod) {
    viz[nod] = 1;
    for (int i = 0; i < graf[nod].size(); i++) {
        int vecin = graf[nod][i];
        if (viz[vecin] == 0)
            dfs(vecin);
    }
}

int main() {
    fin >> n >> m;
    graf.resize(n + 1);
    viz.resize(n + 1, 0);

    for (int i = 0; i < m; i++) {
        int a, b;
        fin >> a >> b;
        graf[a].push_back(b);
        graf[b].push_back(a);
    }

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

    fout << comp;
    return 0;
}