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

ifstream f("dfs.in");
ofstream g("dfs.out");

const int NMAX = 100000;
vector<int> G[NMAX + 1];
int vis[NMAX + 1];
void DFS(int x)
{
	vis[x] = 1;
	for (auto next : G[x])
		if (!vis[next])
			DFS(next);
}

int main()
{
	int n, m;
	f >> n >> m;
	for (int i = 1;i <= m; i++)
	{
		int x, y;
		f >> x >> y;
		G[x].push_back(y);
		G[y].push_back(x);
	}
	int cc = 0;
	for (int i = 1; i <= n; i++) {
		if (!vis[i]) {
			cc++;
			DFS(i);
		}
	}
	g << cc;

	return 0;
}