I tried. 

use strict;
use warnings;
use Data::Dumper;

my @IDs = qw(Apple Apple Grape Banana Banana);
my @Price = qw(5 5 2 3 4 );
my @Amount = qw(10 15 3 4 4 );

sub uniqjoin { 
    my %seen;
    my $sep=shift;
    return join($sep, grep { !$seen{$_}++ } sort  @_);
}

my ($idx, $id, %h);
#to hash of array
while( ($idx,$id)= each(@IDs) ){
    push @{$h{$id}->{price}} , $Price[$idx];
    push @{$h{$id}->{amount}}, $Amount[$idx];
}
#concatenate arrays with '/'
foreach my $id (keys %h){
    $h{$id}->{price} = uniqjoin( '/', @{$h{$id}->{price}} );
    $h{$id}->{amount} = uniqjoin( '/',  @{$h{$id}->{amount}} );
}

#print
print join(' ', sort keys(%h)) . "\n";
print join(' ' , map{ $h{$_}->{price} } sort keys(%h) ) . "\n";
print join(' ' , map{ $h{$_}->{amount} } sort keys(%h) ) . "\n";

[download]
Sometimes I see List::Util and List::MoreUtil at Monk. I should see them.

In reply to Re^2: Arrays merges and redundancies by remiah
in thread Arrays merges and redundancies by Anonymous Monk

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