LeetCode-345. Reverse Vowels of a String

问题：https://leetcode.com/problems/reverse-vowels-of-a-string/?tab=Description
Write a function that takes a string as input and reverse only the vowels of a string.
反转字符中的元音字符。
Example 1:Given s = “hello”, return “holle”.
Example 2:Given s = “leetcode”, return “leotcede”.
Note:The vowels does not include the letter “y”.
分析:调用函数，先判断是否为元音字母。头的和尾的调转。
C++代码：

class Solution {public:    string reverseVowels(string s) {        int i=0;        int j=s.length()-1;        while(i<j){            while(isVowel(s[i])==false && (i<j)){                i++;            }            while(isVowel(s[j])==false && (i<j)){                j--;            }            swap(s[i],s[j]);            i++;            j--;        }        return s;    }    bool isVowel(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;        else        return false;    }};