Computer Science / Unit 3 CS 0099 short lesson, about 20 seconds
The Map
Captions available
The idea
A map is an abstract data type holding unordered associations between key-value pairs, each key appearing exactly once — also called a dictionary, terms bound to definitions.
In practice
A station code looks up its station name; the code is the key, the name the value.
Where people slip
One key, one appearance — that rule is load-bearing.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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