DSA Patterns
15 patterns from arrays to graphs. Master logic and efficiency.
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Interview Session: Two Sum (Optimal)
const twoSum = (nums, target) => { const map = new Map(); // I'm thinking... if I use a hashmap here // I can look up values in O(1) for (let i = 0; i < nums.length; i++) { const complement = target - nums[i]; if (map.has(complement)) { return [map.get(complement), i]; } map.set(nums[i], i); } };
AI Interviewer
"Exactly right. Walk me through what you'd store in the hashmap and how you'd handle the lookup."
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Communication
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Understanding
25%
How to score well
Clarify requirements, name edge cases, explain your approach, and give time/space complexity in your own words.
Problem-Solving
25%
How to score well
Break the task down, compare approaches, debug with evidence, and improve from brute force toward an efficient solution.
Code Quality
20%
How to score well
Pass the tests, keep the algorithm efficient, use readable names, and structure the solution so another engineer can review it.
Communication
30%
How to score well
Think out loud, answer follow-up questions directly, narrate tradeoffs, and explain fixes as you make them.
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Your Metrics
Last 30 days
+12%
78%Ready
Arrays92%
FAANG avg
Trees75%
FAANG avg
Graphs58%
FAANG avg