#!/usr/bin/perl -w
use strict;

my @arr = (1..15) ;
my ($offset,$offset1) ;
$offset = $offset1 = int((scalar @arr)/3);

$offset++ if (scalar @arr % 3 > 0) ;
$offset1++  if (scalar @arr % 3 > 1) ;

my ($arr1, $arr2, $arr3) =
([@arr[0..$offset-1]],[@arr[$offset..$offset+$offset1-1]],[@arr[$offset+$offset1..scalar @arr -1]]);

print $_."\n"  for ((@$arr1,("\n"),@$arr2),("\n"),@$arr3);