链表逆转

下列代码的功能是返回带头结点的单链表L的逆转链表。
List Reverse( List L )
{
    Position Old_head, New_head, Temp;
    New_head = NULL;
    Old_head = L->Next;

    while ( Old_head ) 
     {
        Temp = Old_head->Next;
        
		***Old_head->Next = New_head;//(3分);***  

        New_head = Old_head;  
        Old_head = Temp; 
    }
    
		***L->Next = New_head;//(3分);***

    return L;
}