The Front Desk Finds You in One Scan: Dictionaries

Find any of a gym's 2,000 members in one step, 600 times an hour, with the dictionary your language already has: add, read, update and remove entries, read a missing key safely, and know when not to count on its order.

Updated

Cheat sheet: The Front Desk Finds You in One Scan: Dictionaries
Category
Data Structures
Level
Apprentice
Tags
data structures, Dictionary (data-structures), Dictionary (python), Dictionary<TKey, TValue>, HashMap (java), map() (javascript)