Join same hash of arrays values - perl

Question

I have a hash with a certain set of data. I need to manipulate the hash values so that I can get result like below:
Expected Output:
key_1=Cell1
Val_1=C3#C4#C1#C2
Script:
#!/usr/bin/perl
use strict; use warnings;
use Data::Dumper;
use List::Util qw /uniq/;
my %hash = (
'Cell1' => {
'A' => [ 'C1','C2','C1','C2' ],
'B' => [ 'C3','C3','C4','C4' ]
}
);
print Dumper(\%hash);
my $i = 0;
foreach my $key (keys %hash) {
++$i;
print "key_$i=$key\n";
foreach my $refs (keys %{ $hash{$key} }) {
print "Val_$i=", join('#', uniq #{$hash{$key}{$refs}})."\n";
}
}
Current Output:
key_1=Cell1
Val_1=C3#C4
Val_1=C1#C2
How can I get the expected output here?

Answer 1

You can use an additional array (#cells) to store the values before you print:
foreach my $key (keys %hash) {
++$i;
print "key_$i=$key\n";
my #cells;
foreach my $refs (keys %{ $hash{$key} }) {
push #cells, #{$hash{$key}{$refs}};
}
print "Val_$i=", join('#', uniq #cells)."\n";
}
Prints:
key_1=Cell1
Val_1=C3#C4#C1#C2
The order is not guaranteed since you retrieve the keys from a hash. You could use sort to make the order predicatable.

Answer 2

The shown code uses values for each key one at a time (for A, then for B ...) . Instead, assemble all values using map on the list of all keys
my $i = 0;
for my $key (keys %hash) {
++$i;
say "key_$i=$key";
say "Val_$i=",
join "#", uniq map { #{ $hash{$key}->{$_} } } keys %{$hash{$key}};
}