cirosantilli/project-euler-solutions 2026-01-30
Project Euler solutions 2026-01-30
Repositories of numerical solutions:
Repositories of code solutions:
- euler.stephan-brumme.com/ large number of solutions in C++, stopped around 600. Informal permissive license, e.g. at: euler.stephan-brumme.com/243/Asked for a more formal open license at: github.com/stbrumme/euler/issues/7All of my solutions can be used for any purpose and I am in no way liable for any damages caused.
- www.ivl-projecteuler.com/home 330+ solutions in Python as of 2025. Random looking problem selection. On GitHub: github.com/igorvanloo/Project-Euler-Explained under Unlicense license, a public domain license.
- www.nayuki.io/page/project-euler-solutions. Large number of solutions, mostly in Java and Python primarily but also Mathematica and Haskell sometimes. Proprietary license.
Repositories with hints but no solutions:
Project Euler problem style 2026-01-30
Project Euler problems typically involve finding or proving and then using a lemma that makes computation of the solution feasible without brute force. There is often an obvious brute force approach, but the pick problem sizes large enough such that it is just not fast enough, but the non-brute-force is.
news.ycombinator.com/item?id=7057408 which is mega high on Google says:
I love project euler, but I've come to the realization that its purpose is to beat programmers soundly about the head and neck with a big math stick. At work last week, we were working on project euler at lunch, and had the one CS PhD in our midst not jumped up and explained the chinese remainder theorem to us, we wouldn't have had a chance.
In many cases, the efficient solution involves dynamic programming.
There are also a set of problems which are very numerical analysis in nature and require the approximation of some real number to a given precision. These are often very fiddly as I doubt most people can prove that their chosen hyperparameters guarantee the required precision.
Many problems ask for solution modulo some number. In general, this is only so that C/C++ users won't have to resort to using an arbitrary-precision arithmetic library and be able to fit everything into
uint64 instead. Maybe it also helps the judge system slightly having smaller strings to compare. The final modulos usually don't add any insight to the problems.Bibliography:
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AtCoder 2026-01-30
Saw this one mentioned on some Project Euler forum threads.
Euler Circle 2026-01-30
Nice motto, knowledge olympiads:
Serious mathematics for serious high-school students: There is more to mathematics than competitions.
Lean autoformatter 2026-01-30
TODO none? Seriously?
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Knowledge olympiads are stupid 2026-01-30
Knowledge olympiads are events that trick young kids into thinking that they are making progress, but only serve to distract them from what really matters, which is to dominate a state of the art as fast as possible, contact researches in the area, and publish truly novel results.
There are unlisted articles, also show them or only show them.