[leetCode]344. 反转字符串

csdn:https://blog.csdn.net/renweiyi1487/article/details/109328163

题目

链接:https://leetcode-cn.com/problems/reverse-string

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 char[] 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。

你可以假设数组中的所有字符都是 ASCII 码表中的可打印字符。

示例 1:

输入:["h","e","l","l","o"]
输出:["o","l","l","e","h"]
示例 2:

输入:["H","a","n","n","a","h"]
输出:["h","a","n","n","a","H"]

双指针

思路: 定义双指针left与right,让后交换指针所指元素,如果left>=right则交换结束

class Solution {
    public void reverseString(char[] s) {
        int left = 0, right = s.length - 1;
        while (left < right) {
            char temp = s[left];
            s[left] = s[right];
            s[right] = temp;
            left++;
            right--;
        }
    }
}
posted @ 2020-10-28 10:50  消灭猕猴桃  阅读(80)  评论(0编辑  收藏  举报