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Track 09 of 10
Data StructuresIntermediate Level~30 Mins
9. Trees & Binary Search Trees (BST)
Master hierarchical node structures, BST insertion, search, and tree traversals.
The "WHY" Core Principle
A BST enforces the invariant: left subtree values < root, right subtree values > root.
Interactive Visualizer
Interactive Binary Search Tree (BST) Visualizer
Insert custom nodes, search values step-by-step, or animate In-Order/Pre-Order/Post-Order traversals.
Python BST Node Logic
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class BSTNode:
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def __init__(self, val):
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self.val = val
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self.left = None
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self.right = None
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def insert(root, val):
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if not root: return BSTNode(val)
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if val < root.val:
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root.left = insert(root.left, val)
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else:
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root.right = insert(root.right, val)
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return root
Live Traversal Sequence (INORDER):Visited 0 / 0 Nodes
Press "Play Traversal" or "Step" to watch node visits...
Interactive Code Snippets (1 Lessons)
Lesson 01
BST Node Insertion & In-Order Traversal
O(log N) Search, O(N) TraversalO(N)
Build a Binary Search Tree and print sorted elements via In-Order Traversal.
WHY Under The Hood:
In-Order Traversal recursively visits Left -> Root -> Right.
CPython C Struct Detail: Tree nodes are connected via `node.left` and `node.right` heap references.
BST Node Insertion & In-Order Traversal
Pyodide WASM EngineType, edit code, and click 'Run & Profile' to see live runtime ms and operation count!
Python 3.12 Code (Editable)
Expected:Time: O(log N) Search, O(N) TraversalSpace: O(N)