#include<fstream>
#define dim 100002
#include<vector>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
vector<int >G[dim];
int n,m,a,b,i,nr;bool viz[dim]={0};
void dfs(int nod){
	viz[nod]=1;
	for(int i=0;i<G[nod].size();++i){
		
		if(!viz[G[nod][i]]){
			dfs(G[nod][i]);
		}
		
	}
}
int main (){
	f>>n>>m;
	for(i=1;i<=m;i++){
		f>>a>>b;
		G[a].push_back(b);
		G[b].push_back(a);
	}
	nr=0;
	for(i=1;i<=n;i++)
		if(viz[i]==0){
			dfs(i);
			++nr;
		}
	g<<nr;
	return 0;
}