https://leetcode-cn.com/problems/reverse-linked-list/
点击查看【bilibili】
题目
反转一个单链表。
进阶:
你可以迭代或递归地反转链表。你能否用两种方法解决这道题?
示例
输入: 1->2->3->4->5->NULL
输出: 5->4->3->2->1->NULL
解答
方法1:通过栈的方式实现反转,后进先出
方法2:
答案
var reverseList = function(head) {
let prev = null
let curr = head
let next = head
while(curr !==null) {
next = curr.next // next指向当前节点下一个节点
curr.next = prev // 当前节点的下一位指向prev位置
prev = curr // prev 指向当前节点
curr = next // 当前节点指向next节点
}
return prev
};
var reverseList = function(head) {
let prev = null
let curr = head
while(curr !==null) {
[curr.next,prev,curr] = [prev,curr,curr.next]
}
return prev
};