Case specific sorting of string

It is done using Counting sort

def case_specific_sort(s):
    # Initialize the count arrays for lowercase and uppercase characters
    lower_count = [0] * 26
    upper_count = [0] * 26
 
    # Count the occurrence of each lowercase and uppercase character
    for char in s:
        if char.islower():
            lower_count[ord(char) - ord('a')] += 1
        else:
            upper_count[ord(char) - ord('A')] += 1
 
    # Combine the sorted lowercase and uppercase characters
    sorted_chars = []
    for i in range(26):
        sorted_chars.extend([chr(ord('a') + i)] * lower_count[i])
        sorted_chars.extend([chr(ord('A') + i)] * upper_count[i])
 
    # Convert the list of characters back to a string
    sorted_string = "".join(sorted_chars)
 
    return sorted_string
 
 
s = "hELLOwORLD"
sorted_string = case_specific_sort(s)
print(sorted_string) # Output: ehllloorDW