#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

int n, m, x, y, contor;
vector <int> A[100005];
bool vizitat[100005];

void DFS(int nod) {
    vizitat[nod] = true;
    for (int i = 0; i < A[nod].size(); ++i) {
        int vecin = A[nod][i];
        if (!vizitat[vecin]) {
            DFS(vecin);
        }
    }
}

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

    for (int i = 1; i <= n; ++i) {
        if (!vizitat[i]) {
            ++contor;
            DFS(i);
        }
    }
    fout << contor;
}