Longest common substring — DSA Technical Interview Questions & Answers

Longest common substring

Longest common substring

  • Longest common substring 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 Longest common substring.
  • From the example next to this theory: Longest common substring: dry-run [4, 1, 3].
  • Trap: unbalanced BST becoming a list. Fix that before you talk about advanced DSA.
  • Viva: what is Longest common substring? Then show left < root < right. Then name the trap.

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

Code Examples for Longest common substring

Longest common substring — working example

# Longest common substring
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)

Longest common substring: dry-run [4, 1, 3]. Say the list after one step.

How to Explain Longest common substring to an Interviewer

What is Longest common substring?

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

Give one small example of Longest common substring.

left < root < right Longest common substring: dry-run [4, 1, 3]

What mistake do beginners make with Longest common substring?

unbalanced BST becoming a list Show the fix

Where do you use Longest common substring?

a file explorer folder on disk