1119. Remove Vowels from a String

Given a string S, remove the vowels 'a', 'e', 'i', 'o', and 'u' from it, and return the new string.

Example 1:

Input: "leetcodeisacommunityforcoders"
Output: "ltcdscmmntyfrcdrs"

Example 2:

Input: "aeiou"
Output: ""

Note:

1. S consists of lowercase English letters only.

2. 1 <= S.length <= 1000

解题要点：

先设一个含有元音的set，遍历字符串，把不是元音的字符加到新string里，返回它。

class Solution(object):
    def removeVowels(self, S):
        """
        :type S: str
        :rtype: str
        """
        res = ""
        vset = {'a','e','i','o','u'}
        for s in S:
            if s not in vset:
                res += s
        return res