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Sum of all elements of N-ary Tree

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Sum of all elements of N-ary Tree

Sum of all elements of N-ary Tree sits in a file explorer. Farhan’s job is folder on disk. Write that first.

Sum of all elements of N-ary Tree on the board: left < root < right. Then say what folder on disk looks like after.

Without Sum of all elements of N-ary Tree, a file explorer gets messy and folder on disk is hard to trust.

Use Sum of all elements of N-ary Tree when folder on disk must stay clear. If a simpler DSA step works, use that instead.

If folder on disk breaks under Sum of all elements of N-ary Tree, check unbalanced BST becoming a list first.

After Sum of all elements of N-ary Tree, Farhan should still remember unbalanced BST becoming a list.

Close Sum of all elements of N-ary 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 Sum of all elements of N-ary Tree. Name the trap: unbalanced BST becoming a list.

Example

# Sum of all elements of N-ary Tree
data = [4, 1, 3]
print("start", data)
if data[0] > data[1]:
    data[0], data[1] = data[1], data[0]
print("after one step", data)

Sum of all elements of N-ary Tree: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefSum of all elements of N-ary Tree — Farhan uses it for folder on disk in a file explorer.
RuleSum of all elements of N-ary Tree → left < root < right.
RememberSum of all elements of N-ary Tree + time vs memory (a file explorer).
UseSum of all elements of N-ary Tree in a file explorer (folder on disk).
TrapSum of all elements of N-ary Tree — unbalanced BST becoming a list.
ExSum of all elements of N-ary Tree → folder on disk.

DSA · Theory

Sum of all elements of N-ary Tree

← All stacks

Theory

372/810

Sum of all elements of N-ary Tree

Sum of all elements of N-ary Tree sits in a file explorer. Farhan’s job is folder on disk. Write that first.

Sum of all elements of N-ary Tree on the board: left < root < right. Then say what folder on disk looks like after.

Without Sum of all elements of N-ary Tree, a file explorer gets messy and folder on disk is hard to trust.

Use Sum of all elements of N-ary Tree when folder on disk must stay clear. If a simpler DSA step works, use that instead.

If folder on disk breaks under Sum of all elements of N-ary Tree, check unbalanced BST becoming a list first.

After Sum of all elements of N-ary Tree, Farhan should still remember unbalanced BST becoming a list.

Close Sum of all elements of N-ary 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 Sum of all elements of N-ary Tree. Name the trap: unbalanced BST becoming a list.

Example

# Sum of all elements of N-ary Tree
data = [4, 1, 3]
print("start", data)
if data[0] > data[1]:
    data[0], data[1] = data[1], data[0]
print("after one step", data)

Sum of all elements of N-ary Tree: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefSum of all elements of N-ary Tree — Farhan uses it for folder on disk in a file explorer.
RuleSum of all elements of N-ary Tree → left < root < right.
RememberSum of all elements of N-ary Tree + time vs memory (a file explorer).
UseSum of all elements of N-ary Tree in a file explorer (folder on disk).
TrapSum of all elements of N-ary Tree — unbalanced BST becoming a list.
ExSum of all elements of N-ary Tree → folder on disk.

Sum of all elements of N-ary Tree

Example

Short notes

Questions

Sum of all elements of N-ary Tree

Example

Short notes

Questions