#include <iostream>
#include<vector>
vector <int>v[100001];
using namespace std;
void dfs( int nod)
{   seen[nod]=1;
    for(i=0;i<=v[nod].size();i++)
        if(seen[v[nod][i]==0)
            dfs(v[nod][i]);
}
int main()
{
    ifstream in("dfs.in");
    ofstream out("dfs.out");
    cin>>N>>M;
    for(i=0;i<M;i++){
       cin>>a>>b;
       v[a].push_back(b);
       v[b].push_back(a);
    }
    nr=0;
    for(i=1;i<=N;i++)
        if(seen[i]==0)
         {
              dfs(i);
              nr++;
         }

    return 0;
}