"""

Reverse Vowels of a String

Given a string, reverse only the vowels while keeping all other characters

in their original positions.

Reference: https://leetcode.com/problems/reverse-vowels-of-a-string/

Complexity:

Time: O(n) where n is the length of the string

Space: O(n) for the character list

"""

from __future__ import annotations

def reverse_vowel(text: str) -> str:

"""Reverse only the vowels in a string.

Args:

text: The input string.

Returns:

A new string with vowels reversed.

Examples:

>>> reverse_vowel("hello")

'holle'

"""

vowels = "AEIOUaeiou"

left, right = 0, len(text) - 1

characters = list(text)

while left < right:

while left < right and characters[left] not in vowels:

left += 1

while left < right and characters[right] not in vowels:

right -= 1

characters[left], characters[right] = (

characters[right],

characters[left],

)

left, right = left + 1, right - 1

return "".join(characters)