#include<fstream>
#include<vector>
#define NMAX 100005
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int>adj[NMAX];
long long int n,m,a,b, viz[100000]={}, count=0;
void dfs(int nod)
{
    viz[nod]=1;
    for(int i=0;i<adj[nod].size();++i)
    {
        if(!viz[adj[nod][i]])
        {
            dfs(adj[nod][i]);
        }
    }

}
int main ()
{
        fin>>n>>m;
        for(int i=1;i<=m;++i)
        {
            fin>>a>>b;
            adj[a].push_back(b);
            adj[b].push_back(a);
        }
        for(int i=1;i<=n;++i)
        {
            if(viz[i]==0)
            {
                count++;
                dfs(i);
            }
        }
        fout<<count;
}