# 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.

![Cheat sheet: The Front Desk Finds You in One Scan: Dictionaries](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/2a7cab09afea456588d001e3bbdbc3f8.webp)

- Category: Data Structures
- Level: Apprentice
- Tags: data structures, Dictionary (data-structures), Dictionary (python), Dictionary<TKey, TValue>, HashMap (java), map() (javascript)
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/ds-dictionaries-cheat-sheet