344. 反转字符串 (opens new window)

Description

Difficulty: 简单

Related Topics: 递归 (opens new window), 双指针 (opens new window), 字符串 (opens new window)

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"]

提示：

• 1 <= s.length <= 10⁵
• s[i] 都是 码表中的可打印字符

Solution

Language: JavaScript

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

var reverseString = function(s) {
    let left = 0, right = s.length - 1
    while (left < right) {
        [s[left], s[right]] = [s[right], s[left]]
        left++
        right--
    }
}