345. Reverse Vowels of a String

Python

 
class Solution:
    def reverseVowels(self, s):
        """
        :type s: str
        :rtype: str
        """
        s = list(s)
        left = 0
        right = len(s) - 1
        while right > left:
            if not self.is_vowels(s[left]):
                left += 1
            if not self.is_vowels(s[right]):
                right -= 1
            if self.is_vowels(s[left]) and self.is_vowels(s[right]):
                tmp = s[left]
                s[left] = s[right]
                s[right] = tmp
                left += 1
                right -= 1
        return ''.join(s)

    def is_vowels(self, s):
        if s.lower() in ['a', 'e', 'i', 'o', 'u']:
            return True
        else:
            return False