Counting Letters
20-minute lesson · module-lab-counting-letters
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Counting Letters
20-minute lesson · module-lab-counting-letters
- Build a dictionary by accumulating counts inside a loop.
- Recognize when a single-purpose counter generalizes into a tallying dictionary.
- Handle keys that may or may not already exist in a dictionary.
Source attribution
Status: adapted
How to Think Like a Computer Scientist: Interactive Edition — source · Labs / Counting Letters
Adaptation notes. Reading rewritten in our voice. Generalizes the single-letter counter pattern from the source lab into a full character-tally dictionary. Hidden tests are newly authored and check both populated and edge-case strings.
License notes. Original lab is GNU FDL 1.3 (Brad Miller and David Ranum, 2011). No verbatim text from the original is reproduced here.