#include <bits/stdc++.h>

using namespace std;

vector <int> graph[100005];
int visited[100005];

void dfs(int node) {
	visited[node] = 1;
	for (auto x : graph[node]) {
		if (visited[x]) continue;
		dfs(x);
	}
}

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;
		graph[x].push_back(y);
		graph[y].push_back(x);
	}

	int components = 0;
	for (int i = 1; i <= n; ++i) {
		if (visited[i]) continue; // daca face parte dintr-o componenta anterioara, merg mai departe
		components++; // cresc numarul de componente
		dfs(i); // vizitez componenta lui i
	}
	cout << components;
	return 0;
}