Procedural doubly list

list.cpp

struct List
{
	struct Node
	{
		Node* Next = nullptr;
		Node* Prev = nullptr;
		int Data;
	};

	Node* First = nullptr;
	Node* Last = nullptr;
};

void InitList(List& list, int data)
{
	list.First = new List::Node();
	list.First->Data = data;
	list.First->Next = list.First;
	list.First->Prev = list.First;
	list.Last = list.First;
}

void PushFront(List& list, int data)
{
	if (!list.First)
	{
		InitList(list, data);
		return;
	}
	List::Node* node = new List::Node();
	node->Data = data;
	node->Next = list.First;
	node->Prev = list.Last;
	list.First->Prev = node;
	list.Last->Next = node;
	list.First = node;
}

void PushBack(List& list, int data)
{
	if (!list.First)
	{
		InitList(list, data);
		return;
	}
	List::Node* node = new List::Node();
	node->Data = data;
	node->Next = list.First;
	node->Prev = list.Last;
	list.First->Prev = node;
	list.Last->Next = node;
	list.Last = node;
}

void Destroy(List& list)
{
	while (list.First && list.First != list.Last)
	{
		List::Node* pin = list.First;
		list.First = list.First->Next;
		delete pin;
	}
	if (list.First)
	{
		delete list.First;
	}
	list.First = nullptr;
	list.Last = nullptr;
}

int main()
{
	List list;
	PushFront(list, 1);
	PushFront(list, 2);
	PushFront(list, 3);
	Destroy(list);
	Destroy(list);
	PushFront(list, 1);
	Destroy(list);
	PushBack(list, 1);
	PushBack(list, 2);
	PushBack(list, 3);
	Destroy(list);
	Destroy(list);
	PushBack(list, 1);
	Destroy(list);
}