#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector <int> G[100005];
vector <int>::iterator it;
vector <int> viz;
void dfs(int u,int cc)
{
    int v,i;
    viz[u]=cc;
    for(i=0;i<G[u].size();i++)
    {
        v=G[u][i];
        if(!viz[v])
           dfs(v,cc);
    }
    ///u devine black
}
int main()
{
    int n,m,u,v,i,cc;
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        fin>>u>>v;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    viz.assign(n+1,0);
    cc=0;
    for(i=1;i<=n;i++)
    {
        if(!viz[i])///if(viz[i]==0)
        {
            ++cc;
            dfs(i,cc);
        }
    }
    fout<<cc<<"\n";
    return 0;
}