struct Node* copyRandomList(struct Node* head) {
    struct Node* cur = head;

    //在每个节点后面复制节点
    while(cur)
    {
        struct Node* copy = (struct Node*)malloc(sizeof(struct Node));
        copy->val = cur->val;
        copy->next = cur->next;
        cur->next = copy;
        cur = copy->next;
    }
    cur = head;

    //复制random

    while(cur)
    {
        struct Node* copy = cur->next;
        if(cur->random == NULL)
        {
            copy->random = NULL;
        }
        else
        {
            copy->random = cur->random->next;
        }
        cur = copy->next;
    }

    //分离两个链表
    cur = head;
    struct Node* newHead = NULL;
    struct Node* newTail = NULL;
    while(cur)
    {
        struct Node* copy = cur->next;
        if(newHead == NULL)
        {
            newHead = newTail = copy;
            
        }
        else{
            newTail->next = copy;
            newTail = newTail->next;
        }
        cur = copy->next;
    }

    return newHead;


	
}