#include <iostream>
#include <vector>

// numarul de componente conexe

using namespace std;

const int NMAX = 1e5 + 2;
vector<int> adj[NMAX];
bool viz[NMAX];

void dfs(int nod)
{
	viz[nod] = 1;
	for (auto& to : adj[nod])
	{
		if (!viz[to]) {
			dfs(to);
		}
	}
}

int main()
{
	freopen("dfs.in", "r", stdin);
	freopen("dfs.out", "w", stdout);
	int n , m; cin >> n >> m;
	for (int i = 1; i <= m; i++)
	{
		int x, y; cin >> x >> y;
		adj[x].push_back(y);
		adj[y].push_back(x);
	}

	int nrComp = 0;

	for (int nod = 1; nod <= n; nod++)
	{
		if (!viz[nod]) {
			dfs(nod);
			nrComp++;
		}
	}
	cout << nrComp << '\n';
}