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

int viz[100000], componenta, n, m;
vector<int> adj[100000];
ifstream fin("dfs.in");
ofstream fout("dfs.out");

void dfs(int start) {
	for(vector<int>::iterator it = adj[start].begin(); it != adj[start].end(); ++it) {
		if(viz[*it] == 0) {
			viz[*it] = 1;
			dfs(*it);
		}
	}
}

int main() {
	int i, u, v;
	fin >> n >> m;
	for(i = 0; i < m; i++) {
		fin >> u >> v;
		u--, v--;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	for(i = 0; i < n; i++) {
		if(viz[i] == 0) {
			viz[i] = 1;
			componenta++;
			dfs(i);
		}
	}
	fout << componenta;
	return 0;
}