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

using namespace std;

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

vector<bool> viz;
vector<vector<int>> vec;

void dfs(const int nod_de_start) {
    int nod_curent = nod_de_start;
    viz[nod_curent] = true;

    for (int i : vec[nod_curent]) {
        if (!viz[i]) {
            dfs(i);
        }
    }
}

int main() {
    int n, m;
    fin >> n >> m;

    viz.resize(n + 1, false);
    vec.resize(n + 1);

    for (int i = 0; i < m; i++) {
        int nod1, nod2;
        fin >> nod1 >> nod2;
        vec[nod1].push_back(nod2);
        vec[nod2].push_back(nod1);
    }

    int ctc = 0;

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

    fout << ctc << "\n";

    return 0;
}