Traversing strings

12-minute lesson · module-strings-03

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Traversing strings

12-minute lesson · module-strings-03

  • Iterate character-by-character with `for ch in s:`.
  • Combine traversal with the count and accumulator patterns.
  • Use `in` to test membership.

Source attribution

Status: adapted

How to Think Like a Computer Scientist: Interactive Edition source · Strings / Traversal and the for loop

Adaptation notes. Reading rewritten in our voice. Vowel-counting exercise authored specifically for PyTutor AI.

License notes. Verify chapter-level license metadata on Runestone before copying any text verbatim. This lesson contains no verbatim quotations.