my $credit = [
    {
        (map {$_ => 1.0} qw(g6 g7 g8 g9)),
        (map {$_ => 0.5} qw(g0 g1 g2 g3 g4 g5
                            k0 k1 k2 k3 k4 k5)),
    },
];

##</code><code>##

if (exists $credit->[$qnum]{$answer})
{
    print "Q $qnum: ", $credit->[$qnum]{$answer}, " points\n";
}
else
{
    print "wrong\n";
}