#include<fstream>
#include<vector>
using namespace std;
vector < int >vectoras[99999];
ifstream cin("dfs.in");
ofstream cout("dfs.out");
long nr=0,vizitat[99999],ns,n,m;
void dfs(int ns)
{
    vizitat[ns]=1;
    for(unsigned long i=0;i<vectoras[ns].size();i++)
    {
        if(vizitat[vectoras[ns][i]]==0)
        dfs(vectoras[ns][i]);
    }
}
int main()
{
        cin>>n>>m;
       for(unsigned long i=1;i<=m;i++)
       {
           int x,y;
           cin>>x>>y;
           vectoras[x].push_back(y);
           vectoras[y].push_back(x);
       }
       for(unsigned long i=1;i<=n;i++)
       {
           if(vizitat[i]==0){
            dfs(i);
            nr++;
           }
       }
       cout<<nr;
}