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

using namespace std;

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

void dfs(int node, vector<vector<int>>& edges, vector<bool>& viz) {
	viz[node] = true;

	// for (auto nxt : edges[node]) {
	for (int i = 0; i < edges[node].size(); i++) {
		int nxt = edges[node][i];
		if (!viz[nxt]) {
			dfs(nxt, edges, viz);
		}
	}
}

int main() {
	int n, m; in >> n >> m;

	vector<vector<int>> edges(n);
	for (int i = 0; i < m; i++) {
		int a, b; in >> a >> b;
		a--; b--;
		edges[a].push_back(b);
		edges[b].push_back(a);
	}

	vector<bool> viz(n);
	int cnt_cc = 0;
	for (int i = 0; i < n; i++) {
		if (!viz[i]) {
			cnt_cc++;
			dfs(i, edges, viz);
		}
	}

	out << cnt_cc << "\n";
	return 0;
}