30     Pointers->Prev = P;  in addPointer()
32   P->Prev = nullptr;  in addPointer()
54   if (P->Prev)  in removePointer()
55     P->Prev->Next = P->Next;  in removePointer()
57     P->Next->Prev = P->Prev;  in removePointer()
81   if (Old->Prev)  in replacePointer()
82     Old->Prev->Next = New;  in replacePointer()
84     Old->Next->Prev = New;  in replacePointer()
85   New->Prev = Old->Prev;  in replacePointer()
113     Root->Prev = this;  in DeadBlock()
116   Prev = nullptr;  in DeadBlock()
132   if (Prev)  in free()
133     Prev->Next = Next;  in free()
135     Next->Prev = Prev;  in free()