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.

Solution Stats

108 Solutions

70 Solvers

Last Solution submitted on Feb 15, 2026

Last 200 Solutions

Solution Comments

Show comments
Loading...

Problem Recent Solvers70

Suggested Problems

More from this Author71

Problem Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!