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.
class Solution {
public:
RandomListNode *copyRandomList(RandomListNode *head) {
if(head == NULL)return NULL;
RandomListNode *p,*newp;
p = head;
while(p != NULL)
{
newp = new RandomListNode(p->label);
newp->next = p->next;
p->next = newp;
p = p->next->next;
}
RandomListNode *h = head->next;
newp = h;
p = head;
while(1)
{
if(p->random)newp->random = p->random->next;
p = p->next->next;
if(!p)break;
newp = newp->next->next;
}
newp = h;
p = head;
while(1)
{
p->next = p->next->next;
if(newp->next)newp->next = newp->next->next;
p = p->next;
newp = newp->next;
if(!newp)break;
}
return h;
}
};