js乱序算法中,有一段代码是“[arr[i], arr[j]] = [arr[j], arr[i]]”,这种写法是什么意思?


这种写法是JavaScript中的数组解构赋值和交换元素的一种方式。在JavaScript中,数组的直接赋值实际上是将数组的引用赋值,而不是复制数组的内容。`[arr[i], arr[j]] = [arr[j], arr[i]]` 的意思是: 1. 首先,它创建了一个新的数组 `[arr[j], arr[i]]`,这个新数组的顺序与原数组 `arr` 中的第 `i` 和 `j` 个元素相反。 2. 然后,它用这个新数组来解构赋值给原始数组 `arr`,即将 `arr[i]` 赋值为 `arr[j]`,`arr[j]` 赋值为 `arr[i]`。 这样就实现了 `arr[i]` 和 `arr[j]` 两个元素的交换,而不需要使用额外的临时变量。这是一种简洁的交换两个数组元素的方法,特别是在处理大型数组时,可以避免创建额外的数组。 [2024-05-03 21:44:25 | AI写代码神器 | 215点数解答]
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