Re: Finding Previous and Next in a HASH

my %nxt;
my %prev;

my $prv;
for (sort { $a <=> $b } keys %hash) {
 if (defined $prv) {
  $nxt{$prv} = $_;
  $prev{$_} = $prv;
 }
 $prv = $_;
}
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Re: Re: Finding Previous and Next in a HASH by turnstep (Parson) on Dec 12, 2000 at 07:31 UTC
This is a good answer, but it fails to point the first element "back" to the last, and the last "forward" to the first. Here's one way to do that: `my %nxt; my %prev; my $prv; my $first; for (sort { $a <=> $b } keys %hash) { $first \|\|= $_; if (defined $prv) { $nxt{$prv} = $_; $prev{$_} = $prv; } $prv = $_; } $nxt{$prv}=$first; $prev{$first}=$prv;`	[reply]