No it isn't
just some syntax - look at the starting hash in the OP - the problem revolves around the converting the original hash from a flattened linked list to a hash containing the equivalent linked list ... not just rewriting the hash definition..
FWIW, I've solved it thusly:
use warnings;
use strict;
use Data::Dumper;
my $fll= {
(4,-1),
(2,6),
(6,4),
(3,5),
(5,-1),
(99,-1),
};
my $ll = {};
sub doit {
my $done = { %$fll };
while (%$done) {
foreach (keys %$done) {
my ($k,$v) = ($_, $done->{$_});
if ($v < 0) {
%$ll = (%$ll, ($k, $v));
delete $done->{$k};
} else {
if (exists $ll->{$v}) {
$ll->{$k} = {$v => $ll->{$v}};
delete $done->{$k};
delete $ll->{$v};
}
}
}
}
}
doit();
print Dumper $fll,$ll;
gives:
pointo1d@pointo1d-laptop:~$ perl tst.pl
$VAR1 = {
'6' => 4,
'99' => -1,
'4' => -1,
'3' => 5,
'2' => 6,
'5' => -1
};
$VAR2 = {
'99' => -1,
'3' => {
'5' => -1
},
'2' => {
'6' => {
'4' => -1
}
}
};
As, I think, required
Update:
Added my attempt at a solution.
A user level that continues to overstate my experience :-))
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