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".

代码如下:

 public class Solution {
     public String reverseVowels(String s) {
         ArrayList<Character> list=new ArrayList<>();
         char[] ss=s.toCharArray();
         list.add('a');
         list.add('e');
         list.add('i');
         list.add('o');
         list.add('u');
         list.add('A');
         list.add('E');
         list.add('I');
         list.add('O');
         list.add('U');
         int i=0,j=s.length()-1;
         while(i<j)
         {
             while(!list.contains(ss[i])&&i<j)
             i++;
             while(!list.contains(ss[j])&&i<j)
             j--;

             char c=ss[i];
             ss[i]=ss[j];
             ss[j]=c;

             i++;j--;
         }
         s=String.valueOf(ss);
         return s;
     }
 }