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

const int NMAX = 100005;

vector<int> graf[NMAX];
int viz[NMAX];
int N, M;

void DFS(int nod) {
    viz[nod] = 1;
    for (int vecin : graf[nod]) {
        if (!viz[vecin])
            DFS(vecin);
    }
}

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

    fin >> N >> M;

    for (int i = 0; i < M; i++) {
        int x, y;
        fin >> x >> y;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }

    int nr_comp = 0;
    for (int i = 1; i <= N; i++) {
        if (!viz[i]) {
            nr_comp++;
            DFS(i);
        }
    }

    fout << nr_comp << "\n";

    fin.close();
    fout.close();
    return 0;
}