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Print a Binary Tree in Vertical Order

Theory

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Print a Binary Tree in Vertical Order

Don’t start Print a Binary Tree in Vertical Order with jargon. Start with folder on disk. That is the whole point.

Print a Binary Tree in Vertical Order order: meaning → left < root < right → one limit. Dumping ten features helps nobody.

Without Print a Binary Tree in Vertical Order, a file explorer gets messy and folder on disk is hard to trust.

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

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

After Print a Binary Tree in Vertical Order, Dev should still remember unbalanced BST becoming a list.

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

Exam tip

Say Print a Binary Tree in Vertical Order in one breath, then left < root < right, then 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))

Print a Binary Tree in Vertical Order — inorder walks left → node → right (sorted order for a BST).

Short notes

DefPrint a Binary Tree in Vertical Order — Dev uses it for folder on disk in a file explorer.
RulePrint a Binary Tree in Vertical Order → left < root < right.
RememberPrint a Binary Tree in Vertical Order + time vs memory (a file explorer).
UsePrint a Binary Tree in Vertical Order in a file explorer (folder on disk).
TrapPrint a Binary Tree in Vertical Order — unbalanced BST becoming a list.
ExPrint a Binary Tree in Vertical Order → 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))

Print a Binary Tree in Vertical Order

Example

Short notes

Questions

Print a Binary Tree in Vertical Order

Example

Short notes

Questions