//scrie programul il incarci pe infoarea de 100 p si primul task este indeplinit
//I m watching
#include<vector>
#include<fstream>
using namespace std;

int viz[100005],n,m,x,y,cnt=0;
vector <int> A[100001];
ifstream fin("dfs.in");
ofstream fout("dfs.out");

void citeste_graf()
{
	int i;
	fin>>n>>m;
	for(i=1;i<=m;i++)
	{
		fin>>x>>y;
		A[x].push_back(y);
		A[y].push_back(x);
	}
	fin.close();
}

void df(int nod)
{
	int nr_vecini,i;
	viz[nod]=1;
	nr_vecini=A[nod].size();
	for(i=0;i<nr_vecini;i++)
		if(viz[A[nod][i]]==0)
		df(A[nod][i]);
}

int main()
{
	int i;
	citeste_graf();
	for(i=1;i<=n;i++)
	if(viz[i]==0)
	{
		cnt++;
		df(i);
	}
	fout<<cnt;
	fout.close();
	return 0;
}
//compilez?da