#include <bits/stdc++.h>

using namespace std;

void dfs(int s, vector<vector<int>> &adj, vector<int> &visited)
{
	visited[s] = 1;
	for (int i : adj[s])
		if (!visited[i])
			dfs(i, adj, visited);
}

int main()
{
	freopen("dfs.in", "r", stdin);
	freopen("dfs.out", "w", stdout);
	int n, m;
	cin >> n >> m;

	vector<vector<int>> adj(n + 3, vector<int>());

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

	vector<int> visited(n + 3, 0);


	int cnt = 0;
	for (int i = 1; i <= n; ++i)
		if (!visited[i]) {
			++cnt;
			dfs(i, adj, visited);
		}

	cout << cnt << '\n';
	return 0;
}