copy-list-with-random-pointer

class Solution {
public:
    RandomListNode *copyRandomList(RandomListNode *head) {
        if(!head)return head;
        RandomListNode*pNode=head;
        while(pNode)
        {
            RandomListNode*temp=new RandomListNode(pNode->label);
            temp->next=pNode->next;
            pNode->next=temp;
            pNode=temp->next;
        }
        pNode=head;
        while(pNode&&pNode->next)
        {
            RandomListNode*pNext=pNode->next;
            if(pNode->random)pNext->random=pNode->random->next;
            pNode=pNext->next;
        }
        pNode=head;
        RandomListNode*pClonHead=head;
        while(pNode&&pNode->next)
        {
            RandomListNode*pNext=pNode->next;
            pNode->next=pNext->next;
            pNode=pNext;
        }
        return pClonHead;
    }
};