#include <fstream>
#include <vector>

using namespace std;

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

const int N_MAX = 1e5;
vector<int> adj[N_MAX];
bool visited[N_MAX]{};

void dfs(int node){
	visited[node] = true;

	for(auto neighbour: adj[node])
		if(!visited[neighbour])
			dfs(neighbour);
}

int main(){
	int n, m, a, b;
	fin >> n >> m;
	for(int i = 0; i < m; ++i){
		fin >> a >> b;
		--a;
		--b;

		adj[a].push_back(b);
		adj[b].push_back(a);
	}

	int componente = 0;
	for(int node = 0; node < n; ++node)
		if(!visited[node]){
			++componente;
			dfs(node);
		}

	fout << componente;

	fin.close();
	fout.close();
	return 0;
}