Fin listens for the part an interviewer would question.
You know how to solve it. You fall apart explaining it.
LeetCode taught you to solve it silently. Fin makes you explain it out loud — and flags the gaps before a real interviewer does.
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# Two Sum
# Find two numbers that add to target
# return their indices
# hash map for linear time
# Arrays & Hashing
Fin
Coach
You jumped to the hash map without saying what it stores. Name that invariant before you code.
As I scan, the map stores each value's index so I can check whether the target complement has already appeared.
See it in action
One explanation. One correction. One better take.
Fin listens for the part an interviewer would question, then makes you say it again before you hide behind the code.
Fin
Coach · Two Sum
Fin
Two Sum. Before you code, give me the plan in three sentences.
You
I'd check every pair, then use a hash map for one pass.
Fin
You skipped the invariant: what does the map store, and when do you check it? Say that part again.
You
As I scan, the map stores each value's index. I check for the target complement before storing the current value.
Fin
Better. You named the state and the order of operations. That sounds reasoned, not memorized.
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Do the first rep before you decide. Hear one thing to tighten. Say it again better.
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