Reverse vowels of a string

class Solution:
    def reverseVowels(self, s: str) -> str:
        lst = list(s)
        left = 0
        right = len(s) - 1
        vowels = ['a', 'A', 'e', 'E', 'i', 'I', 'o', 'O', 'u', 'U']
        while left < right:
            if lst[left] in vowels and lst[right] in vowels:
                lst[left], lst[right] = lst[right], lst[left]
                left += 1
                right -= 1
            elif lst[left] in vowels:
                right -= 1
            else:
                left += 1

        return "".join(lst)

Reverse Vowels of a String

Difficulty: Easy

Given a string s, reverse only all the vowels in the string and return it.

The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in both lower and upper cases, more than once.

 

Example 1:

Input: s = "hello"
Output: "holle"

Example 2:

Input: s = "leetcode"
Output: "leotcede"

 

Constraints:

  • 1 <= s.length <= 3 * 105
  • s consist of printable ASCII characters.