反转字符串

反转字符串

力扣题号344

题目描述：

编写一个函数，其作用是将输入的字符串反转过来。输入字符串以字符数组 s 的形式给出。

不要给另外的数组分配额外的空间，你必须原地修改输入数组、使用 O(1) 的额外空间解决这一问题。
示例 1：
输入：s = ["h","e","l","l","o"]
输出：["o","l","l","e","h"]
示例 2：
输入：s = ["H","a","n","n","a","h"]
输出：["h","a","n","n","a","H"]

一道比较简单的题目，利用双指针可以迅速的解决

双指针

class Solution {
    public void reverseString(char[] s) {
		int i = 0;
		int j = s.length-1;
		while (i < s.length /2){
			char tmp;
			tmp = s[i];
			s[i] = s[j];
			s[j] = tmp;
			i++;
			j--;
		}

    }
}