#include <fstream>
#include <vector>
#include <cmath>

using namespace std;

ifstream cin("dfs.in");
ofstream cout("dfs.out");

const int NMAX = 100005;

int n, m;
int insule;
bool vizitat[NMAX];
vector <int> Muchii[NMAX];

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


int main()
{
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int x, y;
        cin>>x>>y;
        Muchii[x].push_back(y);
        Muchii[y].push_back(x);
    }
    for (int i = 1; i <= n; i++) {
        if (!vizitat[i]) insule++, DFS(i);
    }
    cout << insule;
    return 0;
}