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

const int  maxx = 100001;
bool viz[maxx];
vector<int> parcurgere[maxx];


void DFS(int x) {
	viz[x] = true;
	for (int i = 0; i < parcurgere[x].size(); i++) {
		if (!viz[parcurgere[x][i]]) {
			DFS(parcurgere[x][i]);
		}
	}
}

int main() {
	ifstream f("dfs.in");
	ofstream g("dfs.out");
	int n, m, x, y, nr = 0;
	f >> n >> m;

	for (int i = 0; i < m; i++) {
		f >> x >> y;
		parcurgere[x].push_back(y);
		parcurgere[y].push_back(x);
	}


	for (int i = 1; i <= n; i++) {
		if (!viz[i]) {
			nr++;
			DFS(i);
		}
	}
	g << nr;
}