345. Reverse Vowels of a String

1.问题描述

Write a function that takes a string as input and reverse only the vowels of a string.
Example 1:
Given s = “hello”, return “holle”.
Example 2:
Given s = “leetcode”, return “leotcede”.
Note:
The vowels does not include the letter “y”.
来自 https://leetcode.com/problems/reverse-vowels-of-a-string/description/

2.题目分析：

对字符串中的元音经行反转，元音字母有aeiouAEIOU,我们要判断是否是元音，并且存在可交换的元音对。

//我的代码：(beats 39%)
bool isVowel(char c)
{
    string v = "aeiouAEIOU";
    for (int i = 0; i < v.length(); i++)
    {
        if (c == v[i])
            return true;
    }
    return false;
}
string reverseVowels(string &s) 
{
    int i = 0;
    int j = s.length() - 1;
    while (i < j)
    {
        if (!isVowel(s[i]))
        {
            i++;
            continue;
        }
        if (!isVowel(s[j]))
        {
            j--;
            continue;
        }
        swap(s[i], s[j]);
        i++;
        j--;
    }
    return s;
}

//别人家的代码：
string reverseVowels(string s) {
    int i = 0, j = s.size() - 1;
    while (i < j) {
        i = s.find_first_of("aeiouAEIOU", i);
        j = s.find_last_of("aeiouAEIOU", j);
        if (i < j) {
            swap(s[i++], s[j--]);
        }
    }
    return s;
}