逆转字符串中的元音字母 Reverse Vowels of a String

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

class Solution {
public:
    string reverseVowels(string s) {
        int len = s.size();
        if (len <= 1){
            return s;
        }
        int i = 0, j = len - 1;
        while (i < j){
            while (i < j && !isVowels(s[i]))i++;
            while (i < j&&!isVowels(s[j]))j--;
            if (i < j){
                swap(s[i], s[j]);
                i++;
                j--;
            }
        }
        return s;
    }
    bool isVowels(char c){
        if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' ||
            c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U'){
            return true;
        }
        return false;
    }
};