Sort Hash Key and Value simultaneously Perl - perl

Question

I have a hash that I want to sort the keys numerically in ascending order and
its values in ascending alphabetically manner.
#!/usr/bin/perl
use warnings;
use strict;
use List::MoreUtils;
use Tie::IxHash;
my %KEY_VALUE;
#tie %KEY_VALUE,'Tie::IxHash';
my %KEY_VALUE= (
0 => [ 'A', 'C', 'B', 'A' ,'D'],
5 => [ 'D', 'F', 'E', ],
2 => [ 'Z', 'X', 'Y' ],
4 => [ 'E', 'R', 'M' ],
3 => [ 'A', 'B', 'B', 'A' ],
1 => [ 'C', 'C', 'F', 'E' ],
);
#while (my ($k, $av) = each %KEY_VALUE)
#{
# print "$k #$av\n ";
#}
#Sort the key numerically
foreach my $key (sort keys %KEY_VALUE)
{
print "$key\n";
}
#To sort the value alphabetically
foreach my $key (sort {$KEY_VALUE{$a} cmp $KEY_VALUE{$b}} keys %KEY_VALUE){
print "$key: $KEY_VALUE{$key}\n";
}
The wanted input is like this, and I want to print out the sorted keys and values.
%KEY_VALUE= (
0 => [ 'A','A','B','C','D'],
1 => [ 'C','C','E','F' ],
2 => [ 'X','Y','Z' ],
3 => [ 'A', 'A', 'B', 'B' ],
4 => [ 'E','M','R' ],
5 => [ 'D','E','F', ],
);
Additional problem, how to print the key and the scalar value of the first different value
Wanted Output:
KEY= 0 VALUE:0 2 3 4 #The scalar value of first A B C D, start with 0
KEY= 1 VALUE:0 2 3 #The scalar value of first C E F
KEY= 2 VALUE:0 1 2 #The scalar value of first X Y Z
KEY= 3 VALUE:0 2 #The scalar value of first A B
KEY= 4 VALUE:0 1 2 #The scalar value of first E M R
KEY= 5 VALUE:0 1 2 #The scalar value of first D E F

Answer 1

Hash keys have no defined order. Generally you sort the keys as you're iterating through the hash.
The values can be sorted as you iterate through the hash.
# Iterate through the keys in numeric order.
for my $key (sort {$a <=> $b } keys %hash) {
# Get the value
my $val = $hash{$key};
# Sort it in place
#$val = sort { $a cmp $b } #$val;
# Display it
say "$key -> #$val";
}
Note that by default sort sorts in ASCII order as strings. That means sort keys %KEY_VALUE is not sorting as numbers but as strings. sort(2,3,10) is (10,2,3). "10" is less than "2" like "ah" is less than "b". Be sure to use sort { $a <=> $b } for numeric sorting and sort { $a cmp $b } for strings.
You could use a different data structure such as Tie::Ixhash though tying has a significant performance penalty. Generally it's better to sort in place unless your hash gets very large.

Answer 2

You can't sort a hash, you can at best print it sorted (or keep the sorted keys in another array). Finding the position of the first value can be done with first_index; we remove duplicates with uniq.
foreach my $key (sort keys %KEY_VALUE) {
my #value = #{$KEY_VALUE{$key}};
my #indices = map { my $e = $_; first_index { $_ eq $e } #value } (uniq (sort #value));
print "$key: " . (join ', ', #indices) . "\n";
}