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AI DSA & coding interviewer
Arrays to dynamic programming — practice thinking out loud on coding problems, the part most candidates never rehearse.
Free 10-minute interview with a full report. Paid plans run full-length sessions.
Data Structures & Algorithms interview questions you might get
A sample of the starting questions. The live interview follows up on your answer, so no two sessions go the same way.
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Find the length of the longest substring without repeating characters.
What it tests: Sliding window.
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Given a grid of 1s and 0s, count the islands. Then do it without modifying the grid.
What it tests: Graph traversal with a constraint.
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Merge k sorted lists. What's the complexity of your approach?
What it tests: Heaps and analysis.
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Count the ways to climb n stairs taking 1 or 2 steps. Now make it O(1) space.
What it tests: DP and optimization.
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Check whether a binary tree is a valid binary search tree.
What it tests: Recursion with bounds.
How a session works
About 20–30 minutes from setup to report. End any time and you still get feedback on what was covered.
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Set your target
Pick a role, level and stack. Add a job description or your resume if you want questions about your real projects.
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Answer live
Speak or type. The interviewer follows up on thin answers, raises the difficulty when you're doing well and switches to code when it fits.
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Read the notes
A report scores every competency, quotes the answers that cost you, and gives you a prep plan for the next session.
A report that quotes you, not a pat on the back
Every score links back to something you actually said.
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Competency scores
Weighted to the role you picked, so a system design gap counts more for a senior backend role than for a frontend junior.
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STAR check on every story
See which part of each behavioral answer was missing — usually the Result.
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How you sounded
Filler words, hedging, "I" versus "we", and whether you cited real numbers — measured from your words, and compared between the first and second half of the interview.
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A prep plan
The two or three things to practice next, and a skill graph that tracks them across sessions.
Competencies — sample report
STAR — "Tell me about a missed deadline"
How you sounded
Questions
How is this different from a problem site?
Problem sites check whether your code passes. Interviews grade how you think and communicate. This scores your explanation, approach and code together.
Which languages can I use?
Any mainstream language. Name it in the setup.
Can I get hints?
Yes, and the report shows where you used them.
Is it free to try?
Yes. Each month you get a free interview of up to 10 minutes with its scored report. Paid plans add full-length interviews, every track and the full 360 report.