标签：des style blog class code java
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.
思路：这题的关键是如何定位next和random。
1.根据原始链表的每个结点N创建对应的克隆结点N‘，并且把N‘链接在N的后面；
2.设置复制出来的结点的random，假设原始链表上的N的random指向结点S，对应其复制出来的N‘是N的next指向的结点，同样S‘也是S的random指向的结点。也就是如果原始链表上的结点N的random指向S，则它对应的复制结点N‘的random指向S的下一节点S‘;
3.把这个长链表拆分成两个链表：把奇数位置的结点用next连接起来就是原始链表，把偶数位置的结点用next连接起来成为复制出来的结点。
/** * 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) {} * }; */ class Solution { public: void CloneNodes(RandomListNode *pHead) { RandomListNode *pNode=pHead; while(pNode!=NULL) { RandomListNode *pCloned=new RandomListNode(pNode->label); //pCloned->label=pNode->label; pCloned->next=pNode->next; pCloned->random=NULL; pNode->next=pCloned; pNode=pCloned->next; } } void ConnectRandomNodes(RandomListNode *pHead) { RandomListNode *pNode=pHead; while(pNode!=NULL) { RandomListNode *pCloned=pNode->next; if(pNode->random!=NULL) { pCloned->random=pNode->random->next; } pNode=pCloned->next; } } RandomListNode *ReconnectNodes(RandomListNode *pHead) { RandomListNode *pNode=pHead; RandomListNode *pClonedHead=NULL; RandomListNode *pClonedNode=NULL; if(pNode!=NULL) { pClonedHead=pClonedNode=pNode->next; pNode->next=pClonedNode->next; pNode=pNode->next; } while(pNode!=NULL) { pClonedNode->next=pNode->next; pClonedNode=pClonedNode->next; pNode->next=pClonedNode->next; pNode=pNode->next; } return pClonedHead; } RandomListNode *copyRandomList(RandomListNode *head) { CloneNodes(head); ConnectRandomNodes(head); ReconnectNodes(head); } };
Copy List with Random Pointer,布布扣,bubuko.com
标签：des style blog class code java
原文地址：http://www.cnblogs.com/awy-blog/p/3729751.html
