# %seen = ();  # done ONCE
# @array = ([k,v], [k,v], ...);
# ($k,$v) = rhe_3(@array,%seen);

sub rhe_3 (\@\%) {
  my $idx;
  do { $idx = rand @{ $_[0] } } while $_[1]{int $idx}++;
  return @{ $_[0][$idx] };
}