Binary Tree Bootcamp: Full, Complete, & Perfect Trees. Preorder, Inorder, & Postorder Traversal.

[@BackToBackSWE]

Table of Contents: A Quick Message 0:00 - 0:31 What We Are Going To Do 0:31 - 0:52 Full Binary Trees 0:52 - 1:38 Complete Binary Trees 1:38 - 2:14 Perfect Binary Trees 2:14 - 3:18 Let's Discuss The 2 Fundamental Traversals 3:18 - 3:42 How To Know Which Traversal Is Which 3:42 - 5:05 Think of Recursion Like This. 5:05 - 5:33 Preorder Traversal Walkthrough 5:33 - 11:15 Inorder Traversal Walkthrough 11:15 - 14:25 We Realize That This Is A Special Tree 14:25 - 15:07 Postorder Traversal Walkthrough 15:07 - 18:59 Briefly Addressing Time Complexity 18:59 - 19:22 Wrap Up 19:22 - 19:40 At 1:42 I meant that binary heaps are complete binary trees with the heap ordering property. Not that a complete binary tree is always a heap. The code for the traversals is in the description. All recursive and basically the same function. We will do iterative and O(1) space traversals soon.

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[@BackToBackSWE]

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[@maxstanley1818]

two years later, hands down best traversal video on youtube.com. I don't know why schools do not use the nlr rule

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[@BackToBackSWE]

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[@BackToBackSWE]

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5:24 explain very well on nlr (Preorder) traversal on each node, plus recursion in general

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[@BackToBackSWE]

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dude, your explaination helps me retain the information so much better than other tutorials. writing the policy on each node is a really good trick for a visual learner like me. Thanks

[@BackToBackSWE]

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[@BackToBackSWE]

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[@BackToBackSWE]

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[@erc_io]

Great video! Though for me, a better way of remembering which of pre, in, and post maps to which traversal is just understanding what the words mean. In a binary tree, typically all values in the left branch of a node are less than the node itself. The opposite is true for the right branch. Inorder- If you want to traverse the tree "in order", meaning from lowest to highest value, you'd read the left branch values *before* you read the current node's value. Preorder- You read the the current node's value before the left branch values, so you read it *pre* emptively in a sense, with respect to the order of the values low to high. Postorder- You read the current node's value after both the left and right branches, hence, *post*

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[@BackToBackSWE]

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[@BackToBackSWE]

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when I learned heaps in Data Structures and Algorithms, they were taught as a "nearly complete" tree, and what this video calls perfect, our instructor called complete maybe it was near-perfect complete, looking back

[@BackToBackSWE]

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[@BackToBackSWE]

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0:46 full/complete/perfect binary trees 3:48 preorder/inorder/postorder traversal 5:38 preorder and dfs 11:16 inorder and binary search tree 15:07 postorder

[@BackToBackSWE]

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