The code in php that calculates which character appears the most in a string of unknown length

Functions used:
str_split: splits the string into an array. A similar function, explode(), splits a string into an array. array_count_values: used to count the number of occurrences of all the values in an array.
arsort: reverse sort the array and keep the index.
It is primarily used to sort associative arrays where the order of the cells is important. $str = "asdfgfdas323344 # # $$fdsdfg \ * $$$$$* * * * * 443563536254 fas"; // any length string

 
$arr=str_split($str); 
$arr=array_count_values($arr); 
arsort($arr); 
print_r($arr); 

Output:

 
Array 
( 
[$] => 7 
[3] => 6 
[*] => 6 
[4] => 5 
[f] => 5 
[s] => 4 
[d] => 4 
[5] => 3 
[a] => 3 
[6] => 2 
[2] => 2 
[g] => 2 
[#] => 2 
) 

Method 2:
Functions used:
array_unique: removes duplicate values from an array. substr_count: counts the number of times a substring appears in a string.

 
$str="asdfgfdas323344##$\$fdsdfg*$**$*$**$$443563536254fas";// Arbitrary length string  
$arr=str_split($str); 
$unique=array_unique($arr); 
foreach ($unique as $a){ 
$arr2[$a]=substr_count($str, $a); 
} 
arsort($arr2); 
print_r($arr2);