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".
vowels:元音aeiou
解法：two pointers
public class Solution { public String reverseVowels(String s) { String vowel = "aeiouAEIOU"; int start = 0; int end = s.length()-1; char[] chars = s.toCharArray(); while(start<end) { while(start<end&&!vowel.contains(chars[start]+"")) { start++; } while(start<end&&!vowel.contains(chars[end]+"")) { end--; } char temp = chars[start]; chars[start]=chars[end]; chars[end]=temp; start++; end--; } return String.valueOf(chars); } }
chars[end]+"" 这里加上“”很重要，不然会出以下错误：
error: incompatible types: char cannot be converted to CharSequence
原文：http://www.cnblogs.com/hygeia/p/5700019.html