345. Reverse Vowels of a String

Problem:

Write a function that takes a string as input and reverse only the vowels of a string.

Example 1:

Input: "hello"
Output: "holle"

Example 2:

Input: "leetcode"
Output: "leotcede"

Note:
The vowels does not include the letter "y".

思路：

Solution (C++):

string reverseVowels(string s) {
    int i = 0, j = s.length()-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;
}

性能：

Runtime: 12 ms  Memory Usage: 8.1 MB

思路：

Solution (C++):

性能：

Runtime: ms  Memory Usage: MB