#include <cstdio>
#include <vector>
using namespace std;
vector <int> G[100002];
long viz[100001],cnt,x,y,m,n;
void DFS(long q)
{ long i;
     viz[q]=1;
     for(i=0; i<G[q].size(); ++i)
          if(!viz[G[q][i]])
          DFS(G[q][i]);
        
       
}        
int main()
{ long i;
  freopen("dfs.in","r",stdin);
  freopen("dfs.out","w",stdout);

  scanf("%ld %ld",&n,&m);
    for(i=1;i<=m;i++)
      {
        scanf("%ld %ld",&x,&y);
        G[x].push_back(y);
        G[y].push_back(x);
      }
   for(i=1; i<=n; ++i)
       if(!viz[i])
        {cnt++;
        DFS(i);
        }
   printf("%ld",cnt);
   return 0;
}