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

using namespace std;

#define NMAX 100000

ifstream fin("dfs.in");
ofstream fout("dfs.out");
#define cin fin
#define cout fout

vector<int> vecini[NMAX + 1];
bitset<NMAX + 1> vizitat;

void dfs(int n) {
	vizitat[n] = true;
	for (int i = 0; i < vecini[n].size(); i++) {
		if (!vizitat[vecini[n][i]]) {
			dfs(vecini[n][i]);
		}
	}
}

int main() {
	int n, m, x, y;
	cin >> n >> m;
	for (int i = 0; i < m; i++) {
		cin >> x >> y;
		vecini[x].push_back(y);
		vecini[y].push_back(x);
	}

	int rez = 0;
	for (int i = 1; i <= n; i++) {
		if (!vizitat[i]) {
			dfs(i);
			rez++;
		}
	}
	cout << rez << '\n';
}