This is (will be) CS50x 2025, but this site is not yet ready. Check back on January 1, 2025!

This is CS50

CS50’s Introduction to Computer Science

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David J. Malan
malan@harvard.edu
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CS50x Puzzle Day 2025new
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What’s new for 2025?

Week 0 Scratch
Week 1 C
Week 2 Arrays
Week 3 Algorithms
Week 4 Memory
Week 5 Data Structures
Week 6 Python
Week 7 SQL
Week 8 HTML, CSS, JavaScript
Week 9 Flask
Week 10 The End

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