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