344. 反转字符串

题目

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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"]

解题思路

reverse()方法

/**
 * @param {character[]} s
 * @return {void} Do not return anything, modify s in-place instead.
 */
var reverseString = function(s) {
    return s.reverse();
};

双指针法

/**
 * @param {character[]} s
 * @return {void} Do not return anything, modify s in-place instead.
 */
var reverseString = function(s) {
    let len = s.length;
    let left = 0, right = len - 1;
    while(left < right){
        [s[left],s[right]] = [s[right],s[left]];
        left++;
        right--;
    }
    return s;
};