#include "bits/stdc++.h"
using namespace std;

const int maxN = 1e5 + 100;
vector<int> adj[maxN];
//~ adj[1] = {2,3}
bool visited[maxN];

void dfs (int node) {
	//~ cout << "ENTERING node " << node << '\n';
	visited[node] = true;
	for (int i = 0; i < (int) adj[node].size(); ++i) {
		int child = adj[node][i];
		if (visited[child] == false) {
			dfs(child);
		}
	}
	//~ cout << "EXIT from " << node << '\n';
}

int main () {
	 ios::sync_with_stdio(false);
	 cin.tie(nullptr);
	 cout.tie(nullptr);
	 int n, m;
	 cin >> n >> m;
	 for (int i = 1; i <= m; ++i) {
		 int u,v; //u -> v and v -> u
		 cin >> u >> v;
		 adj[u].push_back(v);
		 adj[v].push_back(u);
	 }
	 int cc = 0;
	 for (int i = 1; i <= n; ++i) {
		 if (visited[i] == false) {
			 dfs(i);
			 ++cc;
		 }
	 }
	 cout << cc << '\n';
}

//~ 7 6
//~ 1 2
//~ 1 3
//~ 2 4
//~ 2 5
//~ 3 6
//~ 3 7