15算法课程 345. Reverse Vowels of a String



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".

solution:

把元音字母都存在一个字符串里，然后每遇到一个字符，就到元音字符串里去找，如果存在就说明当前字符是元音字符

code:

class Solution {
public:
    string reverseVowels(string s) {
        int left = 0, right = s.size() - 1;
        string t = "aeiouAEIOU";
        while (left < right) {
            if (t.find(s[left]) == string::npos) ++left;
            else if (t.find(s[right]) == string::npos) --right;
            else swap(s[left++], s[right--]);
        }
        return s;
    }
};