There is more than one way to do it...

use strict;
use warnings;

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 %cats;

# This solution will gobble @strings.
foreach ( @numbers ) {
    $cats{$_} .= shift( @strings );
}
print "$cats{$_}\n" foreach sort keys %cats;
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