#include <fstream>
#include <vector>
#define NMAX 100005

using namespace std;

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

int n, m, nrCC;
bool vizitat[NMAX];
vector<int> g[NMAX];

void citire() {
    int i, x, y;

    fin >> n >> m;
    for (i = 1; i <= m; i++) {
        fin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
}

void dfs(int nod) {
    int vecin;
    unsigned int i;

    vizitat[nod] = true;
    for (i = 0; i < g[nod].size(); i++) {
        vecin = g[nod][i];
        if (vizitat[vecin] == false)
            dfs(vecin);
    }
 }

void rezolva() {
    int i;

    for (i = 1; i <= n; i++)
        if (vizitat[i] == false) {
            nrCC++;
            dfs(i);
        }

    fout << nrCC;
}

int main() {
    citire();
    rezolva();

    fin.close();
    fout.close();

    return 0;
}