#include <iostream>
#include <cstdio>
#include <vector>
#include <cmath>
#include <algorithm>
#include <iomanip>
using namespace std;

struct quest
{
    int lev;
    bool b;
};

bool ls(quest a, quest b)
{
    return a.lev < b.lev;
}

int main()
{
    //freopen("input.txt","r",stdin);
    int n,k;
    cin >> n >> k;
    vector<quest> a(n);
    for (int i=0;i<n;++i)
    {
        cin >> a[i].lev;
        a[i].b=1;
    }
    int q;
    cin >>q;
    double mn=2000;
    double mx=-1;
    int tickets_found = 0;
    for (int i=0;i<q;++i)
    {
        int s=0;
        for (int j=0;j<(n/k);++j)
        {
            int h;
            cin >> h;
            if (j==0 && a[h-1].b)
                ++tickets_found;
            a[h-1].b=0;
            s+=a[h-1].lev;
        }
        double diff = double(s)/(n/k);
        mn = min(mn,diff);
        mx = max(mx,diff);
    }
    if (tickets_found<k) {
        sort(a.begin(),a.end(),ls);
        int i=0;
        int s=0;
        for (int j=0;j<n;j++) {
            if (a[j].b)
            {
                s+=a[j].lev;
                ++i;
            }
            if (i>=(n/k)) break;
        }
        double diff = double(s)/(n/k);
        if (i>=n/k)
            mn=min(mn,diff);

        i=0;
        s=0;
        for (int j=n-1;j>=0;j--) {
            if (a[j].b)
            {
                s+=a[j].lev;
                ++i;
            }
            if (i>=(n/k)) break;
        }
        diff = double(s)/(n/k);
        if (i>=n/k)
            mx=max(mx,diff);
    }
    cout << setprecision (10) <<mn <<' ' <<mx <<endl;
}