•Re: Comparing values in a hash

Do it by inverting the hash:

my %revhash;
while (my($k, $v) = each %hash) {
  push @{$revhash{$v}}, $k;
}
for my $val (sort { $a <=> $b } keys %revhash) {
  my @keys = @{$revhash{$_}};
  if (@keys > 1) { # only items where there's a tie
    print "$val is shared by @keys\n";
  }
}
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-- Randal L. Schwartz, Perl hacker

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Re: •Re: Comparing values in a hash by VSarkiss (Monsignor) on Sep 06, 2002 at 00:21 UTC
I presume you're doing the first `each` loop for clarity of exposition; can't you just do: `my %revhash = reverse %hash;`Or am I missing something?	[reply] [d/l] [select]
•Re: Re: •Re: Comparing values in a hash by merlyn (Sage) on Sep 06, 2002 at 00:28 UTC
No, that won't make an arrayref for the values. That'll have the second value at the same key overwrite the first. -- Randal L. Schwartz, Perl hacker	[reply]
Re: •Re: Comparing values in a hash by cens (Novice) on Sep 06, 2002 at 00:07 UTC
Thank you very much. I feel like an idiot...should have known that.	[reply]