#include "iostream"
#include "fstream"
using namespace std;

int math[10][10], nod[10]; 
int m, n;


void dfs(int nod_start)
{
	nod[nod_start] = 1;
	for (int i = 1; i <= n; i++)
	if (!nod[i] && math[nod_start][i])
		dfs(i);
}

int main()
{
	int x, y;
	int numarator = 0;
	ifstream dfs_in;
	ofstream dfs_out;
	dfs_in.open("dfs.in");
	dfs_out.open("dfs.out");
	if (dfs_in.fail())
	{
		cerr << "Eroare la deschiderea fisierului";
		exit(1);
	}
	/*citire*/
	dfs_in >> n >> m;
	for (int i = 1; i <= m; i++)
	{
		dfs_in >> x >> y;
		math[x][y] = 1;
		math[y][x] = 1;
	}
	/*dfs*/
	for (int i = 1; i <= n; i++)
	if (!nod[i])
	{
		numarator++;
		dfs(i);
	}
	dfs_out << numarator;
}