#include <bits/stdc++.h>
using namespace std;
#define Nmax 100013
vector <int> G[Nmax];
int n,i,j,m,a,b,comp(0);
bool used[Nmax];

void dfs(int node)
 {
 used[node]=1;
 vector <int>::iterator it;
 for (it=G[node].begin();it!=G[node].end();++it)
     if (!used[*it]) dfs(*it);
 }

int main(void)
{
 ifstream in("dfs.in");
 ofstream out("dfs.out");
 in>>n>>m;
 while(m--)
   {
   	in>>a>>b;
   	G[a].push_back(b);
   	G[b].push_back(a);
   }
for (i=1;i<=n;++i)
  if (!used[i])
       {
       	++comp;
       	dfs(i);
	   }
 out<<comp<<"\n";	
 return 0;
}