Problem 61021. The Case of the Missing Prototype – Check the Lab’s Logbook for Suspicious Late-Night Entries

Created by Ritik

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After counting the fingerprints, you turn your attention to the security logbook.It records the entry hours (from 0 to 23) of everyone who accessed the Innovation Lab.As per lab policy, no one is allowed inside after 9 PM (21 hours).Every suspicious late-night entry could reveal a key suspect!
Your task is to determine how many entries occurred during these restricted hours.
Given a numeric vector entries, return the number of times people entered the lab at or after 21.

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Last Solution submitted on Oct 24, 2025

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Problem 61021. The Case of the Missing Prototype – Check the Lab’s Logbook for Suspicious Late-Night Entries

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Last 200 Solutions

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Problem Recent Solvers8

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Problem 61021. The Case of the Missing Prototype – Check the Lab’s Logbook for Suspicious Late-Night Entries

Solution Stats

Last 200 Solutions

Solution Comments

Problem Recent Solvers8

Suggested Problems

More from this Author22

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Community Treasure Hunt

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