LeetCode 344. Reverse String（字符串翻转）

原题网址：https://leetcode.com/problems/reverse-string/

Write a function that takes a string as input and returns the string reversed.

Example:

Given s = "hello", return "olleh".
方法：循环。

public class Solution {
public String reverseString(String s) {
if (s == null) return null;
char[] sa = s.toCharArray();
char[] r = new char[sa.length];
for(int i=0; i<sa.length; i++) r[i] = sa[sa.length-1-i];
return new String(r);
}
}