SLOG 7

This week we had our midterm exam, and we spent some lecture time doing some 

review.The new things we learnt this week is the Binary Search Tree. To simplify, I will call 

it BST and the Binary Tree BT.

The only difference between BST and BT is that there is a rule in BST : left child <node< 

right child. Since three is an order among nodes in BST, it will be an extra time for a BST to 

keep its property when doing insert and delete. Also, based on the property, we can exactly 

know whether it goes left or right. Through if statement, we can control the direction of 

Recursive steps.

For example, I would show the way I write method on BST.

def insert (node, data):

      return_node = node

      if not node : 

                     return_node = BTNode(data)

      elif  data < node.data:

                     node.left = insert(node.left, data)

      elif  data > node.data:

                     node.right = insert(node.right, data)

      

      return return_node

Above is just my way of write method insert, and there may also be some other ways. The 

most vital thing is that we create BST to search data more conveniently, so we should not 

make the method very complicated.