Reverse Vowels of a String

 1 public class Solution {
 2     public String reverseVowels(String s) {
 3         if (s == null || s.length() < 2) {
 4             return s;
 5         }
 6         
 7         StringBuilder result = new StringBuilder();
 8         int end = s.length() - 1;
 9         for (int i = 0; i < s.length(); i++) {
10             if (isVowels(Character.toLowerCase(s.charAt(i)))) {
11                 while (end >= 0 && !isVowels(Character.toLowerCase(s.charAt(end)))) {
12                     end--;
13                 }
14                 result.append(s.charAt(end--));
15             } else {
16                 result.append(s.charAt(i));
17             }
18         }
19         return result.toString();
20     }
21     
22     private boolean isVowels(char c) {
23         return c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u';
24     }
25 }

DO NOT forget to move the end index one more. Otherwise, it will keep stucking in same vowel.

posted on 2016-06-29 15:21 keepshuatishuati 阅读(118) 评论(0) 编辑收藏举报