gistfile1.pl

my $total = 0;
while (($id, $weight) = $sth->fetchrow) {
  $total += $weight;
  push @choices, [$total, $id];
}

my $rand = rand($total);
my $chosen = undef;

for my $choice (@choices) {
  if ($choice->[0] >= $rand) {
    $chosen = $choice->[1];
    last;
  }
}

if (!defined $chosen) {
  warn "Can't happen";
}

$word = word($chosen);