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Meet Allison & Tim
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Practice coding interviews out loud with real-time voice coaching. Your code actually runs.
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1Check for Duplicateseasy
2Part 2
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Based onLeetCode
easyBlind 75
Contains Duplicate
Contains Duplicate is a classic scan-and-record problem: the right bookkeeping beats brute force. It's a great warm-up that builds data-structure instincts without a ton of moving parts. Watch your edge cases around repeats, and be clear about what your map is storing.
Arrays & Hashing
👩🏫
👨💼
Meet Allison & Tim
Your AI coaches
Practice coding interviews out loud with real-time voice coaching. Your code actually runs.
Free · No sign up · Early access
1Check for Duplicateseasy
2Part 2
Start Part 1 to unlock your next challenge
Based onLeetCode
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