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Tree Traversal

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Tree Traversal

Asha only reaches for Tree Traversal when folder on disk has to stay correct in a file explorer.

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

Tree Traversal exists so Asha can keep folder on disk correct in a file explorer.

Use Tree Traversal when folder on disk must stay clear. If a simpler DSA step works, use that instead.

Tree Traversal miss — unbalanced BST becoming a list. Fix it before you talk about advanced DSA.

Place Tree Traversal next to nearby DSA work — left < root < right is the link.

Viva for Tree Traversal — what it is → left < root < right → the mistake (unbalanced BST becoming a list).

Exam tip

For Tree Traversal: definition + a file explorer + one failure.

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))

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

Short notes

DefTree Traversal — Asha uses it for folder on disk in a file explorer.
RuleTree Traversal → left < root < right.
RememberTree Traversal + Big-O (a file explorer).
UseTree Traversal in a file explorer (folder on disk).
TrapTree Traversal — unbalanced BST becoming a list.
ExTree Traversal → 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))

Tree Traversal

Example

Short notes

Questions

Tree Traversal

Example

Short notes

Questions