题目

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random指向一个随机节点），请对此链表进行深拷贝，并返回拷贝后的头结点。（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）

代码

/*
struct RandomListNode {
    int label;
    struct RandomListNode *next, *random;
    RandomListNode(int x) :
            label(x), next(NULL), random(NULL) {
    }
};
*/
class Solution {
public:
    RandomListNode* Clone(RandomListNode* pHead)
    {
        RandomListNode *head = pHead, *pHead2;
        if (head == NULL)
        {
            pHead2 = NULL;
        }
        else
        {
            while(head != NULL)
            {
                RandomListNode *p = new RandomListNode(head->label);
                p->next = head->next;
                head->next = p;
                head = head->next->next;
            }
            head = pHead;
            while(head != NULL)
            {
                if (head->random != NULL)
                {
                    head->next->random = head->random->next;
                }
                head = head->next->next;
            }
            RandomListNode *p2 = NULL;
            head = pHead;
            pHead2 = head->next;
            p2 = pHead2;
            head->next = head->next->next;
            head = head->next;

            while(head != NULL)
            {
                p2->next = head->next;
                head->next = p2->next->next;
                p2 = p2->next;
                head = head->next;
            }


        }

        return pHead2;
    }
};