#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

vector<int>v[100005];
int n,m,u,y,viz[100005],nrcomp;
void dfs(int x){
	viz[x]=nrcomp;
	for(auto i:v[x]){
		if(viz[i]==0)
			dfs(i);
	}
}

int main()
{
	fin>>n>>m;
	for(int i=1;i<=m;i++){
		fin>>u>>y;
		v[u].push_back(y);
		v[y].push_back(u);
	}
	for(int i=1;i<=n;i++){
		if(viz[i]==0){
			nrcomp++;
			dfs(i);
		}
	}
	fout<<nrcomp;
    return 0;
}