#include <cstdlib>
#include <iostream>
#include<vector>
#include<stdio.h>

using namespace std;

int N,M,k;
vector <int> a[100001];
int viz[100001];

void dfs(int s)
{ viz[s]=1;

  for( int i=0;i<a[s].size();i++)
    if (!viz[a[s][i]])
     dfs(a[s][i]);
     }



int main()
{
int i,x,y,nr=0;
freopen("dfs.in","r",stdin);
freopen("dfs.out","w",stdout);

scanf("%d %d", &N,&M);

 for(i=0;i<M;i++)
   { scanf("%d %d",&x,&y);

   a[x].push_back(y);
   a[y].push_back(x);
}

for (i=1;i<=N;i++)
 if (!viz[i])
   { nr++;
    dfs(i);
      }

printf("%d",nr);

       return 0;
}