链表题目汇总(python3)

1、从头到尾打印链表

输入一个链表，按链表值从尾到头的顺序返回一个ArrayList。

# -*- coding:utf-8 -*-
class ListNode:def __init__(self, x):self.val = xself.next = Noneclass Solution:def printListFromTailToHead(self, listNode):l =[]while listNode:l.append(listNode.val)listNode = listNode.nextreturn l[::-1]

2、链表中倒数第k个节点

输入一个链表，输出该链表中倒数第k个结点。

# -*- coding:utf-8 -*-
class ListNode:def __init__(self, x):self.val = xself.next = Noneclass Solution:def FindKthToTail(self, head, k):node_list = []while head:node_list.append(head)head = head.nextif k < 1 or k > len(node_list):returnreturn node_list[-k]

3、反转链表

输入一个链表，反转链表后，输出新链表的表头。

# -*- coding:utf-8 -*-
class ListNode:def __init__(self, x):self.val = xself.next = Noneclass Solution:def ReverseList(self, pHead):if pHead is None or pHead.next is None:return pHeadpre = Nonecur = pHeadwhile cur:temp = cur.nextcur.next = prepre = curcur = tempreturn pre

 

待续...