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

bitset<100019> viz;
int n;
vector<int> v[100019];

void citire() {
	ifstream fin("dfs.in");
	int x, y, m;
	fin >> n >> m;
	for(int i = 1; i <= m; i++) {
		fin >> x >> y;
		v[x].push_back(y);
		v[y].push_back(x);
	}
}

void dfs(int nod) {
	viz[nod] = true;
	for(int j = 0; j < v[nod].size(); j++)
		if(viz[v[nod][j]] == false)
			dfs(j);
}

int main() {
	unsigned int nr_comp_conex = 0;

	citire();

	for(int i = 1; i <= n; i++) {
		if(viz[i] == false) {
			nr_comp_conex++;
			dfs(i);
		}
	}

	ofstream fout("dfs.out");

	fout << nr_comp_conex;

}