Tree-Traversal.md

tags	date
algorithm trees traversal-algorithm inorder preorder postorder level-order	1991-05-11

Tree-Traversal

Inorder, Preorder, Postorder, Level Order

Content

• Inorder

• Tree-Traversal Go

• Tree Traversal in Python 🐍

Related

What does preorder | inorder | postorder means?

• Preorder, Inorder, Postorder = flavors of DFS
• Level-order = BFS

🌲 DFS (Depth-First Search)

• General strategy: explore as far down a branch as possible before backtracking.
• In trees, DFS can be expressed in three main orders:
  • Preorder → Visit root → left → right
  • Inorder → Visit left → root → right
  • Postorder → Visit left → right → root
• So preorder is one type of DFS (but not the only one).

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🌳 BFS (Breadth-First Search)

• General strategy: explore neighbors level by level before going deeper.
• In trees, BFS is exactly what we usually call Level-Order traversal.