Python – Extract Sorted Strings

When you need to filter strings that have their characters in sorted order, you can use list comprehension with the sorted() method. A sorted string is one where the characters appear in alphabetical order.

Example

Below is a demonstration of extracting sorted strings from a list ?

my_list = ["pyt", "Fdf", "Fun"]

print("The list is :")
print(my_list)

my_result = [element for element in my_list if ''.join(sorted(element)) == element]

print("The result is :")
print(my_result)

Output

The list is :
['pyt', 'Fdf', 'Fun']
The result is :
['Fdf']

How It Works

The algorithm checks each string by:

• Sorting characters: sorted(element) returns a list of characters in alphabetical order

• Joining back: ''.join(sorted(element)) creates a string with sorted characters

• Comparing: If the sorted version equals the original, the string is already sorted

Multiple Examples

words = ["abc", "zyx", "def", "hello", "ayz"]

sorted_words = [word for word in words if ''.join(sorted(word)) == word]

print("Original words:", words)
print("Sorted words:", sorted_words)

Original words: ['abc', 'zyx', 'def', 'hello', 'ayz']
Sorted words: ['abc', 'def']

Case-Sensitive vs Case-Insensitive

words = ["Abc", "def", "XYZ"]

# Case-sensitive (uppercase letters come first)
case_sensitive = [word for word in words if ''.join(sorted(word)) == word]

# Case-insensitive
case_insensitive = [word for word in words if ''.join(sorted(word.lower())) == word.lower()]

print("Case-sensitive result:", case_sensitive)
print("Case-insensitive result:", case_insensitive)

Case-sensitive result: ['XYZ']
Case-insensitive result: ['Abc', 'def']

Conclusion

Use list comprehension with sorted() to extract strings with alphabetically ordered characters. Remember that sorting is case-sensitive by default, with uppercase letters coming before lowercase letters.