this post was submitted on 22 Feb 2026
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Programmer Humor

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[–] 418_im_a_teapot@sh.itjust.works 4 points 2 hours ago

We could probably improve on that significantly without losing speed.

return $x < 8

That should yield one additional correct answer, while also confusing anyone who thinks it just returns false.

And if we just hard coded and checked the first 20 or so primes before always returning false, we would probably get noticeable improvement (depending on the total range).

[–] HiddenLayer555@lemmy.ml 10 points 4 hours ago

Just put "Precondition: x must not be prime" in the function doc and it'll be 100% accurate. Not my fault if you use it wrong.

[–] Jankatarch@lemmy.world 5 points 3 hours ago

...95.121%
???

[–] Armand1@lemmy.world 5 points 4 hours ago* (last edited 4 hours ago)

I said something similar here about an election fraud detection system with 99.999% accuracy.

https://lemmy.world/comment/22178379

[–] pruwybn@discuss.tchncs.de 7 points 9 hours ago (1 children)

Is this not at all stochastic, or do I just not know what stochastic means?

[–] cypherpunks@lemmy.ml 4 points 7 hours ago

it would be clearer to say that it is stochastically accurate

[–] MeetMeAtTheMovies@hexbear.net 9 points 11 hours ago

Warning: unused variable

Just add it to the pile I guess

[–] rbos@lemmy.ca 8 points 10 hours ago

I've had managers who follow that exact algorithm.

[–] pineapplelover@lemmy.dbzer0.com 9 points 11 hours ago (4 children)

I'm confused, shouldn't this be printing false no matter what the input is?

[–] Couldbealeotard@lemmy.world 6 points 4 hours ago

The output is not the output of the algorithm, it's the output of the unit test.

95% of numbers up to that point at not prime. Testing the algorithm that only says "not prime" is therefore correct 95% of the time. The joke is that, similar to AI, the algorithm is being presented as a useful tool because it's correct often but not always.

[–] Carl@hexbear.net 15 points 11 hours ago* (last edited 11 hours ago)

that's the joke, since most numbers aren't prime, this function is technically highly accurate despite being completely useless.

[–] anton@lemmy.blahaj.zone 5 points 9 hours ago (1 children)

The test suite probably looks something like this:

int tests_passed=0;
int tests_failed=0;
for(int i=0;i<100000;i++){
    printf("test no. %d: ", i);
    if(is_prime(i)==actually_is_prime(i)){
        printf("passed\n");
        tests_passed++;
    }else{
        printf("failed\n");
        tests_failed++;
    }
}
//...
[–] pineapplelover@lemmy.dbzer0.com 3 points 2 hours ago

Ah that makes more sense thanks. So the bottom one is a unit test and not the code being run itself

[–] Evotech@lemmy.world 4 points 9 hours ago (1 children)
[–] Jankatarch@lemmy.world 2 points 3 hours ago* (last edited 3 hours ago)

"AI models have started training other AI models, by pressing The-Button-That-Trains-AI-models; this button was built 7 years ago by a bunch of online volunteers we won't ever credit."

[–] TomMasz@lemmy.world 32 points 15 hours ago (1 children)

95.121% of the time it works everytime.

[–] idriss@lemmy.ml 1 points 1 hour ago

A similar experiment I did comes to mind from 3 years ago.

For the fun of it I was trying to train a few deep neural network configurations (LSTM, a few variations of FCNs, ...) to trade shitcoins and downloaded 4 years of 1h candles.

The first easiest idea was to prepare the training data to fire three signals, buy, sell, do nothing (I know a terrible choice). The cost function was setup to do the simple thing and maximize the overall profit (I know an other terrible choice). Fast forward 30min of training and the final outcome is a model that outputs "do nothing" in 100% of the cases.

[–] sepiroth154@feddit.nl 22 points 15 hours ago* (last edited 15 hours ago) (1 children)

You could simplify it even further by removing the int x parameter of the function...

[–] obelisk_complex@piefed.ca 12 points 14 hours ago

So elegant! This is too valuable for GitHub, sell this directly to the Saudi government.

[–] Thekingoflorda@lemmy.world 14 points 13 hours ago

It approaches 100% accuracy

[–] idriss@lemmy.ml 30 points 16 hours ago (2 children)

I am screenshoting this so it will be screenshot of a screenshot of a screenshot then post it somewhere else

[–] athatet@lemmy.zip 3 points 9 hours ago
[–] SharkAttak@kbin.melroy.org 8 points 13 hours ago

Not even adding some watermark? smh

[–] razen@lemmy.world 4 points 12 hours ago (2 children)

But when the input is all prime numbers then the accuracy is 0.

[–] cypherpunks@lemmy.ml 9 points 12 hours ago

The Simpsons character Rainier Wolfcastle on stage with a microphone, on TV, with the caption "THAT'S THE JOKE"

also btw icymi, this is a post about LLMs

[–] lnxtx@sopuli.xyz 3 points 15 hours ago

But cryptography...