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

my @a = (1..1284);

my $chunkedRef = chunky(@a);

sub chunky {
     #for chunks (chunks = 100 blocks of passed -in array)                                                                                     
     my %master;
     for(0..int @_/100)
     {
         # create an array for each 100 elements and add it to the hash                                                                        
         push @{$master{$_+1 . ' key'}},@a[$_*100..$_*100+100];
     }

     return \%master;
}

print Dumper %$chunkedRef;
1;