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Lesson 14 of 16 · about 16 min

Proving programs correct

Tests check some inputs, but a proof covers all of them. You'll learn loop invariants (a fact that stays true every time around a loop), how to show a loop always stops, and use both to fix a binary search and write an exact square root for huge numbers.

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This lesson is part of the DoingCamp Pass. Members get every lesson in every course, with all the interactive visuals, coding exercises and challenges.

In this lesson you'll learn:

  • Loop invariant
  • Termination
  • Recursion is induction

Free to try in F05 Logic & Proofs:

The first 3 lessons of every course are free, no account needed.