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

my @numbers = ('1','1','1','2','2','3','3','4','4','5','6');
my @strings = ('hello','you','tree','people','fun',
	    'sun','grass','love','food','car','rabbit');
	
my %hash;
	    
for (0..$#numbers){
	$hash{$numbers[$_]} .= $strings[$_];
}

print Dumper(\%hash);
__OUTPUT__
$VAR1 = {
          '6' => 'rabbit',
          '4' => 'lovefood',
          '1' => 'helloyoutree',
          '3' => 'sungrass',
          '2' => 'peoplefun',
          '5' => 'car'
        };