力扣 206. 反转链表

题目描述：

给你单链表的头节点 head ，请你反转链表，并返回反转后的链表。

解析：

Java:

public ListNode reverseList(ListNode head) {
        ListNode prev = null;
        ListNode curr = head;
        ListNode next = head;
        while(curr != null) {
            next = curr.next;
            curr.next = prev;
            prev = curr;
            curr = next;
        }
        return prev;
    }

JavaScript:

var reverseList = function(head) {
    let prev = null;
    let curr = head;
    while(curr !== null) {
        [curr.next, prev, curr] = [prev, curr, curr.next];
    }
    return prev;
};