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Every blog post that took off on Hacker News, ranked by the votes of its best submission. 21,842 posts.

Software Engineering
Any year
15725

A Fairly Fast Fibonacci Function

A common example of recursion is the function to calculate the $n$-th Fibonacci number: def naive_fib(n): if n < 2: return n else: return naive_fib(n-1) + naive_fib(n-2) This follows the mathematical definition very closely but it’s performance is terrible: roughly $\mathcal{O}(2^n)$. This is commonly patched up with…

15733

Stop Misquoting Donald Knuth

DISCLAIMER: The following are my own personal opinions and are not shared, sanctioned or endorsed by anybody in particular, especially my employer. Any criticisms expressed herein are of a general nature and are neither inspired by nor directed at any person, entity, or product in particular. Links to other online…

15734

Fix Your Timestep

Introduction Hi, I’m Glenn Fiedler and welcome to Game Physics. In the previous article we discussed how to integrate the equations of motion using a numerical integrator. Integration sounds complicated, but it’s just a way to advance the your physics simulation forward by some small amount of time called “delta time”…

15740

R7RS versus R6RS (2018)

InPhase asked today on #scheme about the R7RS vs R6RS debate. I followed the original debate closely and have experience both using and implementing R6RS. I also recently added R7RS support in Akku.scm 0.3.0, so I feel like I can weigh in on this. It’s a topic that many feel passionately about, and I’m also firmly on…

15743

How games cheat to help players

If we’ve done our jobs right, Wind-up Knight is a fairly simple game. There are only four inputs, and only two are ever needed simultaneously. Sir Sprint, our heroic spring-loaded knight, runs forward automatically, removing the need for a classic directional pad or analog stick. The challenge is derived from careful…