A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.
Return a deep copy of the list.
解题思路:简单的深拷贝思想,重点在于如何处理random结点,我用的是建立一个原本结点和新建结点的映射.
#include<iostream>
#include<vector>
#include<map>
using namespace std;
//Definition for singly - linked list with a random pointer.
struct RandomListNode {
	int label;
	RandomListNode *next, *random;
	RandomListNode(int x) : label(x), next(NULL), random(NULL) {}
};
RandomListNode *copyRandomList(RandomListNode *head) {
	RandomListNode* TmpHead = head;
	RandomListNode* ResultList = new RandomListNode(0);
	RandomListNode* TmpResultNode = ResultList;
	map<RandomListNode*, RandomListNode*>NodeMap;
	while (TmpHead!=NULL)
	{
		RandomListNode* p = new RandomListNode(TmpHead->label);
		NodeMap.insert(make_pair(TmpHead, p));
		TmpResultNode->next = p;
		TmpResultNode = TmpResultNode->next;
		TmpHead = TmpHead->next;
	}
	TmpHead = head;
	TmpResultNode = ResultList->next;
	while (TmpHead!=NULL)
	{
		if (TmpHead->random != NULL)
			TmpResultNode->random = NodeMap[TmpHead->random];
		TmpHead = TmpHead->next;
		TmpResultNode = TmpResultNode->next;
	}
	return ResultList->next;
}原文:http://blog.csdn.net/li_chihang/article/details/43527629