#include 
#include 

typedef struct LinkNode{
		struct LinkNode*prior;
		struct LinkNode*next;
		int data;
}LinkNode,*LinkList;

int main()
{
	int n;
	LinkList plist = (LinkList)malloc(sizeof(LinkNode));
	LinkNode *pNode,*rear;
	 rear = plist; 
	while(~scanf("%d", &n))
	{	
		if(n == -1)
		continue;
		pNode = (LinkNode*)malloc(sizeof(LinkNode));
		pNode->data = n;
		rear->next = pNode;
		pNode->prior = rear;
		rear = pNode;
		scanf("%d", &n);
		while(n!=-1)
		{	
			pNode = (LinkNode*)malloc(sizeof(LinkNode));
			pNode->data = n;
			plist->next = pNode;
			pNode->prior = rear;
			rear = pNode;
			scanf("%d", &n);
		}
		rear->next = NULL;
		while(rear!=plist)
		{
			printf("%d\n",rear->data);
			rear = rear->prior;
		}
	}
	return 0;

}

//頭插法 
#include 
#include 
typedef struct LinkNode{
		struct LinkNode*next;
		int data;
}LinkNode,*LinkList;
int main()
{
	int n;
	LinkList plist = (LinkList)malloc(sizeof(LinkNode));
	plist->next = NULL; 
	LinkNode *pNode,*rear;
	while(~scanf("%d", &n))
	{	
		if(n == -1)
			continue;
		pNode = (LinkNode*)malloc(sizeof(LinkNode));
		pNode->data = n;
		pNode->next = plist->next;
		plist->next = pNode; 
		scanf("%d", &n);
		while(n!=-1)
		{	
			pNode = (LinkNode*)malloc(sizeof(LinkNode));
			pNode->data = n;
			pNode->next = plist->next;
			plist->next = pNode; 
			scanf("%d", &n);
		}
		rear = plist->next;
		while(rear!=NULL)
		{
			printf("%d\n",rear->data);
			rear = rear->next;
		}
	}
	return 0;
}