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Every blog post that took off on Hacker News, ranked by the votes of its best submission. 80,933 posts.

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25622

AlphaProof's Greatest Hits

Here I’ll try to explain the coolest ideas in each of AlphaProof’s IMO 2024 solutions. AlphaProof produces proofs in Lean, and each Lean proof is composed of a series of tactics. So I’ll pick out the tactics that correspond to these ideas in the proofs for problems 1, 2 and 6 (the three problems that AlphaProof…

25626

PHP 7's new hashtable implementation

About three years ago I wrote an article analyzing the memory usage of arrays in PHP 5. As part of the work on the upcoming PHP 7, large parts of the Zend Engine have been rewritten with a focus on smaller data structures requiring fewer allocations. In this article I will provide an overview of the new hashtable…

25644

Brilliant or insane code?

I came upon a very interesting and cryptic snippet of code somewhere nameless , and I can’t decide if it is brilliant or completely insane. It is a very obscure way of accomplishing the required task, but it’s around four times faster than the alternatives I’ve tried, so I have to admit that it’s not completely…