Question 1

What is InterviewSkool?

Accepted Answer

InterviewSkool is an AI-powered mock interview platform that simulates real FAANG-style coding and system design interviews. An AI interviewer named Alex walks you through every stage: problem clarification, approach design, complexity analysis, coding, and hidden test suite evaluation for coding; requirements, architecture, and deep dives on a whiteboard for system design, and issues a hiring signal at the end.

Question 2

Does InterviewSkool support system design interviews?

Accepted Answer

Yes. Pick a problem (or go random) and a level: SDE-2, SDE-3, or Staff Engineer. You design on an interactive whiteboard while talking through requirements, architecture, and deep dives with Alex, and get a 0–100 score with per-parameter feedback and level readiness.

Question 3

How does the AI interviewer work?

Accepted Answer

Alex is an AI interviewer. It asks probing clarifying questions, validates your approach, challenges your complexity analysis, observes your code against hidden test cases in real time, and adapts its follow-up questions based on your answers, just like a real FAANG engineer would.

Question 4

Which companies does InterviewSkool prepare you for?

Accepted Answer

InterviewSkool currently supports Google, Meta, Amazon, Apple, Microsoft, and many more companies. Problems are sourced from real interviews at those companies and calibrated to the difficulty bar for SDE-1, SDE-2, and SDE-3+ levels.

Question 5

What programming languages can I use?

Accepted Answer

You can code in JavaScript, Python, Java, C++, or TypeScript. Pick the language you are most comfortable with.

Question 6

How is InterviewSkool different from LeetCode?

Accepted Answer

LeetCode is a problem bank, you solve problems alone and get a pass/fail. InterviewSkool simulates the actual interview conversation: Alex asks questions, challenges your reasoning, and evaluates how you communicate, not just whether your code passes. You get a hiring signal and 12-dimension feedback, not just test results.

Question 7

What is a hiring signal?

Accepted Answer

A hiring signal is the recommendation a real interviewer would make after your session: Strong Yes, Yes, Lean Yes, or No. InterviewSkool computes yours from 12 dimensions including code correctness, communication, DSA knowledge, and optimization mindset.

Question 8

How much does InterviewSkool cost?

Accepted Answer

InterviewSkool offers paid plans. Sign in with Google to see current pricing and get started.

Question 9

Is it Interview School or InterviewSkool?

Accepted Answer

InterviewSkool (one word, no space) is a distinct AI-powered mock interview platform at interviewskool.com. People sometimes search for it as 'Interview Skool' (two words), that's the same platform. InterviewSkool is NOT Interview School (interviews.school), which is a different career platform. InterviewSkool focuses on coding execution and technical system design with real-time voice AI.

Problem	Difficulty	Companies	Breakdown / Solution
Binary Tree Maximum Path Sum	Hard	3 companies	View breakdown →
Binary Tree Zigzag Level Order Traversal	Medium	2 companies	View breakdown →
Amount of Time for Binary Tree to Be Infected	Medium	1 companies	View breakdown →
Binary Tree Inorder Traversal	Easy	1 companies	View breakdown →
Binary Tree Preorder Traversal	Easy	1 companies	View breakdown →
Binary Tree Vertical Order Traversal	Medium	1 companies	View breakdown →
House Robber III	MEDIUM	1 companies	View breakdown →
Lowest Common Ancestor of a Binary Tree II	MEDIUM	1 companies	View breakdown →
Lowest Common Ancestor of a Binary Tree III	MEDIUM	1 companies	View breakdown →
Lowest Common Ancestor of a Binary Tree IV	MEDIUM	1 companies	View breakdown →
Step-By-Step Directions From a Binary Tree Node to Another	Medium	1 companies	View breakdown →
Vertical Order Traversal of a Binary Tree	HARD	1 companies	View breakdown →
Populating Next Right Pointers in Each Node	Medium	5 companies	View breakdown →

Binary Tree Interview Questions

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