How do I implement a binary search tree in Python?

How do I implement a binary search tree in Python?

To implement a binary search tree (BST) in Python, you can start by defining a Node class that represents each node in the tree.

What methods should I include in the BST class?

You should include methods for insertion, deletion, searching, and traversing the tree (in-order, pre-order, post-order).

Can you show me an example of the insertion method?

Sure! Here's a simple insertion method:

class BST:
    def __init__(self):
        self.root = None

    def insert(self, key):
        if self.root is None:
            self.root = Node(key)
        else:
            self._insert_rec(self.root, key)

    def _insert_rec(self, node, key):
        if key < node.value:
            if node.left is None:
                node.left = Node(key)
            else:
                self._insert_rec(node.left, key)
        else:
            if node.right is None:
                node.right = Node(key)
            else:
                self._insert_rec(node.right, key)

What about the traversal methods?

For traversal, you can implement in-order, pre-order, and post-order methods. Here's an example of in-order traversal:

    def in_order(self, node):
        if node:
            self.in_order(node.left)
            print(node.value)
            self.in_order(node.right)