use strict; 
use warnings; 
use 5.010; 
 
my @arr = ('a', 'b', 'c', 'b', 'b', 'c'); 
my %hash; 
 
for (@arr) { 
    $hash{$_}++; 
} 
 
say %hash; 
 
--output:-- 
c2a1b3

use strict; 
use warnings; 
use 5.010; 
 
my @arr = ('a', 'b', 'c', 'b', 'b', 'c'); 
my %hash = ( 
    a => 0, 
    b => 0,  
    c => 0 
); 
 
for my $letter (@arr) { 
    my $count = $hash{$letter}; 
    $hash{$letter} = $count + 1; 
} 
 
say %hash; 
 
--output:-- 
c2a1b3