复杂链表的复制.py

'''
输入一个复杂链表（每个节点中有节点值，以及两个指针，
一个指向下一个节点，另一个特殊指针指向任意一个节点），返回结果为复制后复杂链表的head。
'''

# -*- coding:utf-8 -*-
class RandomListNode:
    def __init__(self, x):
        self.label = x
        self.next = None
        self.random = None
class Solution:
    # 返回 RandomListNode
    def Clone(self, pHead):
        if pHead == None:
            return None
        self.CloneNodes(pHead)
        self.ConnectRandomNodes(pHead)
        return self.ReconnectNodes(pHead)
    # 复制原始链表的每个结点, 将复制的结点链接在其原始结点的后面
    def CloneNodes(self, pHead):
        pNode = pHead
        while pNode:
            pCloned = RandomListNode(0)
            pCloned.label = pNode.label
            pCloned.next = pNode.next
            # pCloned.random = None         #不需要写这句话, 因为创建新的结点的时候,random自动指向None

            pNode.next = pCloned
            pNode = pCloned.next

    # 将复制后的链表中的复制结点的random指针链接到被复制结点random指针的后一个结点
    def ConnectRandomNodes(self, pHead):
        pNode = pHead
        while pNode:
            pCloned = pNode.next
            if pNode.random != None:
                pCloned.random = pNode.random.next
            pNode = pCloned.next

    # 拆分链表, 将原始链表的结点组成新的链表, 复制结点组成复制后的链表
    def ReconnectNodes(self, pHead):
        pNode = pHead
        pClonedHead = pClonedNode = pNode.next
        pNode.next = pClonedHead.next
        pNode = pNode.next

        while pNode:
            pClonedNode.next = pNode.next
            pClonedNode = pClonedNode.next
            pNode.next = pClonedNode.next
            pNode = pNode.next

        return pClonedHead

node1 = RandomListNode(1)
node2 = RandomListNode(3)
node3 = RandomListNode(5)
node1.next = node2
node2.next = node3
node1.random = node3

S = Solution()
clonedNode = S.Clone(node1)
print(clonedNode.random.label)