Binary tree traversal

Four traversal methods

（ Always remember to write , But I can't find , It was in the draft box , Let's send it out ）

In the sequence traversal

void InorderTraversal(BinTree BT)
{
    
	if (BT)
	{
    
		InorderTraversal(BT->Left);
		printf(" %c", BT->Data);
		InorderTraversal(BT->Right);
	}
}

The first sequence traversal

Recursive writing ：

void PreorderTraversal(BinTree BT)
{
    
	if (BT)
	{
    
		printf(" %c", BT->Data);
		PreorderTraversal(BT->Left);
		PreorderTraversal(BT->Right);
	}
}

Non recursive writing ：

void PreorderPrintLeaves(BinTree BT)
{
    
	BinTree T = BT;
	while (T || !IsEmpty(S)) {
    
		while (T) {
    
			Push(S, T);
			printf("%5d", T->Data);
			T = T->Left;
		}
		if (!IsEmpty(S)) {
    
			T = Pop(S);
			T = T->Right;
		}
	}
}

After the sequence traversal

void PostorderTraversal(BinTree BT)
{
    
	if (BT)
	{
    
		PostorderTraversal(BT->Left);
		PostorderTraversal(BT->Right);
		printf(" %c", BT->Data);
	}
}

Sequence traversal

struct queue {
    
    BinTree Data;
	struct queue* Next;
};
void Pop(BinTree data);// The team 
BinTree Push();// Out of the team 
struct queue* head, * tail;
void LevelorderTraversal(BinTree BT)
{
    
	if (!BT) return;// The empty tree returns directly 
	head = tail = NULL;
	Pop(BT);
	while (tail != NULL&&head!=NULL) {
    
		BinTree T= Push();
		if(T)printf(" %c", T->Data);
		if (T->Left) Pop(T->Left);
		if (T->Right) Pop(T->Right);
	}
}
// The team 
// Simple queue 
void Pop(BinTree data)
{
    
	struct queue* temp = (struct queue*)malloc(sizeof(struct queue));
	temp->Data = data;
	temp->Next = NULL;
	
	if (head == NULL) head = temp;
	else tail->Next = temp;
	tail = temp;
	
}
// Out of the team 
BinTree Push() {
    
	BinTree point = head->Data;
	head = head->Next;
	return point;
}