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Diameter of Binary Tree

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Diameter of Binary Tree

If you can teach Diameter of Binary Tree using folder on disk, you know it. If you only know the heading, you don’t.

Do Diameter of Binary Tree once by hand. left < root < right. Change one input. Say the new result out loud.

Skip Diameter of Binary Tree and unbalanced BST becoming a list shows up in a file explorer.

Diameter of Binary Tree shows up in a file explorer. Name folder on disk, not “a real-world scenario”.

Don’t do this with Diameter of Binary Tree: unbalanced BST becoming a list. Interviewers spot it in ten seconds.

After Diameter of Binary Tree, Meera should still remember unbalanced BST becoming a list.

Close Diameter of Binary Tree with: “If I skip it, folder on disk goes wrong like this: unbalanced BST becoming a list.”

Exam tip

Board: folder on disk. Dry-run Diameter of Binary Tree. Name the trap: unbalanced BST becoming a list.

Example

class Node:
    def __init__(self, val, left=None, right=None):
        self.val, self.left, self.right = val, left, right

def inorder(n):
    if not n:
        return []
    return inorder(n.left) + [n.val] + inorder(n.right)

root = Node(2, Node(1), Node(3))
print(inorder(root))

Diameter of Binary Tree — inorder walks left → node → right (sorted order for a BST).

Short notes

DefDiameter of Binary Tree — Meera uses it for folder on disk in a file explorer.
RuleDiameter of Binary Tree → left < root < right.
RememberDiameter of Binary Tree + time vs memory (a file explorer).
UseDiameter of Binary Tree in a file explorer (folder on disk).
TrapDiameter of Binary Tree — unbalanced BST becoming a list.
ExDiameter of Binary Tree → folder on disk.

class Node: def __init__(self, val, left=None, right=None): self.val, self.left, self.right = val, left, right def inorder(n): if not n: return [] return inorder(n.left) + [n.val] + inorder(n.right) root = Node(2, Node(1), Node(3)) print(inorder(root))

Diameter of Binary Tree

Example

Short notes

Questions

Diameter of Binary Tree

Example

Short notes

Questions