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

using namespace std;

const int NMAX = 100005;

bool viz[NMAX];
vector<int> vec[NMAX];

void dfs(int nod) {
    viz[nod] = true;
    for (int v : vec[nod]) {
        if (!viz[v]) {
            dfs(v);
        }
    }
}

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

    int n, m;
    fin >> n >> m;

    for (int i = 0; i < m; i++) {
        int u, v;
        fin >> u >> v;
        vec[u].push_back(v);
        vec[v].push_back(u);
    }

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

    fout << conex << "\n";

    return 0;
}