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CS 400 · Lecture notes
Last week we used a binary search tree to keep keys in sorted order. This week we trade full ordering for speed: a priority queue only needs to hand back the most important item next.
The usual way to build one is with a heap. Because a heap is a complete binary tree, it fits in an array with no pointers, unlike a hash table with chaining.
Every class has its own language. Margin helps you learn it where you read it, in slides, PDFs, course pages and notes, then hands it back to you as a glossary and a quiz.
How it works
01Highlight any word on any page and press ⌥⇧S, click the pill, or right-click. Margin remembers where you found it, down to the PDF page.
Write the definition in your own words, or let Margin find one that fits your class: textbook glossaries for psych, NIST for CS, science databases for bio and stats.
From then on the term is underlined on Canvas, course pages and every lecture PDF. Hover it and your definition is right there, with the course and where you first saw it. Your email and YouTube stay untouched.
The usual way to build a priority queue is with a heap. Inserting and removing both take logarithmic time.
Because a heap is a complete binary tree, it lives happily in an array.
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Margin reads your course code, so “heap” in CS 400 means the data structure, and “elasticity” in ECON 101 isn't about rubber bands.
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Lecture slides open in Margin's own viewer, with your terms underlined, a list of every term in the file, and dark pages for late nights.
A side panel lists the terms you've saved that appear in this PDF, with links to each page.
Every saved term remembers its source, so one click takes you back to slide 14.
Works on PDFs from course sites and on the ones sitting in your Downloads folder.
Glossary and quiz
Every term lands in a glossary sorted by course. When it's time to review, Margin quizzes you, and the ones you miss come back first.
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