Substring Check — DSA Technical Interview Questions & Answers

Substring Check

Substring Check

  • Substring Check is a DSA topic. In plain words you use it for folder on disk in a file explorer. Don’t start with a slogan — start with that picture.
  • Smallest example: left < root < right. Type it, run it, and say what you see. If you can do that from memory, you know Substring Check.
  • From the example next to this theory: Substring Check: dry-run [4, 1, 3].
  • Trap: unbalanced BST becoming a list. Fix that before you talk about advanced DSA.
  • Viva: what is Substring Check? Then show left < root < right. Then name the trap.

Technical Interview Tip: What is Substring Check? Show this: left < root < right. Trap: unbalanced BST becoming a list.

Code Examples for Substring Check

Substring Check — working example

# Substring Check
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)

Substring Check: dry-run [4, 1, 3]. Say the list after one step.

How to Explain Substring Check to an Interviewer

What is Substring Check?

Used for folder on disk a file explorer Not just the heading

Give one small example of Substring Check.

left < root < right Substring Check: dry-run [4, 1, 3]

What mistake do beginners make with Substring Check?

unbalanced BST becoming a list Show the fix

Where do you use Substring Check?

a file explorer folder on disk