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Reddit Interview Question Bank

Reddit's loop runs on a small, slowly-rotating bank of company-specific coding prompts (Tennis Scoring, Report Chain, Chat Message Merge) paired with product-flavored system-design rounds (Game Leaderboard, Live Chat, Notification System). The bar is high on clean OOD and crisp clarification — multi-part prompts are routinely under-scoped on purpose, and rounds end without finishing all parts. Ads and ML Platform orgs add a hiring-manager domain round on top of the standard loop; recent cohorts also report aggressive down-leveling and long team-match limbo after a passing loop.

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Tennis Match Scoring

Multi-part object-oriented design problem modeling a tennis match. Implement point / game / set / match scoring rules, then extend to best-of-three / best-of-five formats and run-time queries. The most common Reddit phone-screen prompt.

SWE
MLE
object-design
oop-design
simulation
state-machine
+1
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