#include <iostream>
#include <cstdio>
#include <vector>
#include <cmath>
#include <algorithm>
#include <iomanip>
using namespace std;
struct t
{
    int c;
    bool b;
};

bool foo(t a, t l)
{
    return(a.c < l.c);
}

int main()
{
    //freopen("input.txt","r",stdin);
    int n,k;
    cin >>n >>k;

    vector <t> a(n);

    for (int i=0;i<n;++i)
    {
        cin >>a[i].c;
        a[i].b=1;
    }

    int q;
    cin >>q;

    double mn=2000;
    double mx=-1;
    double e=0.00000001;
    for (int i=0;i<q;++i)
    {
        int s=0;
        for (int j=0;j<(n/k);++j)
        {
            int h;
            cin >>h;
            a[h-1].b=0;
            s+=a[h-1].c;
        }
        if (mn - double (double (s)/(n/k)) > e )
            mn= double (double (s)/(n/k));
        if (mx - double (double (s)/(n/k)) < e )
            mx= double (double (s)/(n/k));
    }

    sort(a.begin(),a.end(),foo);

    if (k!=q)
    {

        int i=0;
        int j=0;
        bool f=true;
        int s=0;
        while (f && j<n)
        {


            if (a[j].b==1)
            {
                s+=a[j].c;
                ++i;
            }
            if (i>=(n/k)) f=false;
            ++j;

        }
        if (f==false) if (mn - double (double (s)/(n/k)) > e )
            mn= double (double (s)/(n/k));



        i=0;
        j=n-1;
        f=true;
        s=0;
        while (f && j>=0)
        {
            if (a[j].b==1)
            {
                s+=a[j].c;
                ++i;
            }
            if (i>=(n/k)) f=false;
            --j;
        }
        if (f==false) if (mx - double (double (s)/(n/k)) < e )
            mx= double (double (s)/(n/k));
    }

    cout << setprecision (10) <<mn <<' ' <<mx <<endl;



}