#include <iostream>
#include <algorithm>
#include <fstream>
#include <vector>
#include <queue>
#include <stack>
#include <climits>
#include <set>
#include <string>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int> v[100005];
int viz[100005];
void dfs(int nod) {
	viz[nod] = 1;
	for (auto el : v[nod])
		if (!viz[el]) dfs(el);
}
int main() {
	int n, m;
	fin >> n >> m;
	for (int i = 1; i <= m; i++) {
		int x, y;
		fin >> x >> y;
		v[x].push_back(y);
		v[y].push_back(x);
	}
	int rez = 0;
	for (int i = 1; i <= n; i++)
		if (!viz[i]) {
			rez++;
			dfs(i);
		}
	fout << rez;
}