剑指offer-题26：复杂链表的复制

题目描述

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。（注意，输出结果中请不要返回参数中的节点引用，否则判题程序会直接返回空）

实验平台：牛客网

解决思路：

java:

/*
public class RandomListNode {
int label;
RandomListNode next = null;
RandomListNode random = null;

RandomListNode(int label) {
this.label = label;
}
}
*/
public class Solution {
public RandomListNode Clone(RandomListNode pHead) {
cloneNodes(pHead);
connectRandomNodes(pHead);
return divideList(pHead);
}

// 1.复制复杂链表，并将next指针赋值
public void cloneNodes(RandomListNode pHead) {
RandomListNode node = pHead;
while (node != null) {
RandomListNode cloneNode = new RandomListNode(node.label);
cloneNode.next = node.next;
cloneNode.random = null;
node.next = cloneNode;
node = cloneNode.next;
}
}

// 2.跟复制的链表的random指正赋值
public void connectRandomNodes(RandomListNode pHead) {
RandomListNode node = pHead;
while (node != null) {
RandomListNode cloneNode = node.next;
if (node.random != null) {
cloneNode.random = node.random.next;
}
node = cloneNode.next;
}
}

// 3.将原始的复杂链表和复制的链表分开
public RandomListNode divideList(RandomListNode pHead) {
RandomListNode node = pHead;
RandomListNode cloneListHead = null;
RandomListNode cloneNode = null;
if (node != null) {
cloneListHead = node.next;
cloneNode = node.next;
node.next = cloneNode.next;
node = node.next;
}
while (node != null) {
cloneNode.next = node.next;
cloneNode = cloneNode.next;
node.next = cloneNode.next;
node = node.next;
}
return cloneListHead;
}
}

python:

# -*- 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):
# write code here
self.clone_nodes(pHead)
self.connect_random_nodes(pHead)
return self.divide_list(pHead)

def clone_nodes(self, pHead):
node = pHead
while node is not None:
clone_node = RandomListNode(node.label)
clone_node.next = node.next
node.next = clone_node
node = clone_node.next

def connect_random_nodes(self, pHead):
node = pHead
while node is not None:
clone_node = node.next
if node.random is not None:
clone_node.random = node.random.next
node = clone_node.next

def divide_list(self, pHead):
node = pHead
clone_list_head = None
if node is not None:
clone_list_head = node.next
clone_node = node.next
node.next = clone_node.next
node = node.next
while node is not None:
clone_node.next = node.next
clone_node = clone_node.next
node.next = clone_node.next
node = node.next
return clone_list_head