Here is all i could come up with:
use strict;
my @a = ('a'..'f');
my $hash;
my $last = 1;
for (reverse @a) {
$hash->{$_} = $last;
$last = {$_ => $hash->{$_}};
}
delete $hash->{$a[$_]} for (1..@a);
Hehehe, i waited until
Abigail-II posted first though.
Now i am going to spend some time figuring out how
that works ... need more coffee!
UPDATE: Ok, let's figure Abigail-II's code out ...
When dealing with loops, a good way to understand the code
is to chart out what happens at each iteration -
- Iteration 1:
- @array = ('a','b','c');
- atomic:
- $hash = undef;
- $hash->{a} = $val; # $val = 1
- $val = $hash;
- # is ('b','c') > 1 ? yes
- Iteration 2:
- @array = ('b','c');
- atomic:
- $hash = undef;
- $hash->{b} = $val; # $val = {a => 1}
- $val = $hash;
- # is ('c') > 1 ? no
- Last line: (note that $hash is currently undef)
- $hash->{c} = $val; # $val = {b => {a => 1}}
The key to this code is the atomic triple assignment inside
the while loop. Break that into 3 seperate assignments and
the results are not the same.
Abigail-II++ :)
UPDATE*2:
I think i like Anony's answer the best ...
now that is using Perl to write Perl! /smack forehead
jeffa
L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)