#include <fstream>
#include <vector>
using namespace std;

const int MAXN = 100000;

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

vector<int> adj[MAXN];
bool viz[MAXN];
int N, M;

void dfs(int nod) {
	viz[nod] = true;
	for (int vecin : adj[nod]) {
		if (!viz[vecin]) {
			dfs(vecin);
		}
	}
}

int main() {
	fin >> N >> M;
	for (int i = 0; i < M; i++) {
		int x, y;
		fin >> x >> y;
		adj[x].push_back(y);
		adj[y].push_back(x);
	}

	int componente = 0;
	for (int i = 1; i <= N; i++) {
		if (!viz[i]) {
			componente++;
			dfs(i);
		}
	}

	fout << componente << "\n";
	return 0;
}