Glossary · Phase 7 · Software engineering
Big O
A way to describe how a program's work grows as its input grows, such as O(n) for one loop or O(n²) for a loop inside a loop.
Try it now
Slide to a million: O(n²) takes about 11 days at that speed, and O(n log n) about 20 seconds.
Learn it properly
Algorithm complexity · Count the work code does, and see why some programs stop scaling. About 30 minutes.
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