this post was submitted on 31 Oct 2024
388 points (98.5% liked)

196

16719 readers
2382 users here now

Be sure to follow the rule before you head out.

Rule: You must post before you leave.

^other^ ^rules^

founded 2 years ago
MODERATORS
 
top 50 comments
sorted by: hot top controversial new old
[–] Euphoma@lemmy.ml 82 points 1 month ago (2 children)

return true

is correct around half of the time

[–] ImplyingImplications@lemmy.ca 42 points 1 month ago
assert IsEven(2) == True
assert IsEven(4) == True
assert IsEven(6) == True

All checks pass. LGTM

[–] aliser@lemmy.world 19 points 1 month ago (2 children)
return Math.random() > 0.5

would also be correct about half the time

load more comments (2 replies)
[–] bob_lemon 53 points 1 month ago* (last edited 1 month ago) (2 children)
import re

def is_even(i: int) -> bool:
    return re.match(r"-?\d*[02468]$", str(i)) is not None
[–] lime@feddit.nu 5 points 1 month ago

i was gonna suggest the classic

re.match(r"^(..)\1*$", "0" * abs(i)) is not None
[–] superkret 45 points 1 month ago (3 children)

Just divide the number into its prime factors and then check if one of them is 2.

[–] fartripper@lemmy.ml 20 points 1 month ago* (last edited 1 month ago) (1 children)

or divide the number by two and if the remainder is greater than

-(4^34)

but less than

70 - (((23*3*4)/2)/2)

then

true
[–] superkret 8 points 1 month ago (1 children)

What if the remainder is greater than the first, but not less than the latter?

Like, for example, 1?

[–] prime_number_314159@lemmy.world 3 points 1 month ago (1 children)

Then you should return false, unless the remainder is also greater than or equal to the twenty second root of 4194304. Note, that I've only checked up to 4194304 to make sure this works, so if you need bigger numbers, you'll have to validate on your own.

[–] fartripper@lemmy.ml 5 points 1 month ago (1 children)

i hate to bring this up, but we also need a separate function for negative numbers

load more comments (1 replies)
[–] tipicaldik@lemmy.world 14 points 1 month ago (2 children)

I remember coding actionscript in Flash and using modulo (%) to determine if a number was even or odd. It returns the remainder of the number divided by 2 and if it equals anything other than 0 then the number is odd.

[–] Korne127@lemmy.world 25 points 1 month ago

Yeah. The joke is that this is the obvious solution always used in practise, but the programmer is that bad that they don't know it and use some ridiculous alternative solutions instead.

[–] superkret 19 points 1 month ago

I believe that's the proper way to do it.

[–] Rai@lemmy.dbzer0.com 38 points 1 month ago (2 children)

Zero people in this post get the YanDev reference

[–] urheber@discuss.tchncs.de 8 points 1 month ago (1 children)

so nobody actually really got the joke. very sad Moment.

[–] Rai@lemmy.dbzer0.com 9 points 1 month ago

It’s really just us… I’ve seen the basic programming joke a bunch of times, but people really aren’t understanding the YanDev/font embellishment. Sad indeed.

[–] jbk@discuss.tchncs.de 27 points 1 month ago (1 children)

so did someone draw this by hand or was it a filter

[–] beefbot@lemmy.blahaj.zone 10 points 1 month ago

tbh it looks like an AI broke this down slightly & reconstructed it

[–] gerryflap@feddit.nl 22 points 1 month ago (1 children)

Using Haskell you can write it way more concise:

iseven :: Int -> Bool
iseven 0 = True
iseven 1 = False
iseven 2 = True
iseven 3 = False
iseven 4 = True
iseven 5 = False
iseven 6 = True
iseven 7 = False
iseven 8 = True
...

However, we can be way smarter by only defining the 2 base cases and then a recursive definition for all other numbers:

iseven :: Int -> Bool
iseven 0 = True
iseven 1 = False
iseven n = iseven (n-2)

It's having a hard time with negative numbers, but honestly that's quite a mood

[–] luciferofastora@lemmy.zip 12 points 1 month ago

Recursion is its own reward

[–] lnxtx@feddit.nl 22 points 1 month ago (2 children)

Ask AI:

public static boolean isEven(int number) {
    // Handle negative numbers
    if (number < 0) {
        number = -number; // Convert to positive
    }
    
    // Subtract 2 until we reach 0 or 1
    while (number > 1) {
        number -= 2;
    }
    
    // If we reach 0, it's even; if we reach 1, it's odd
    return number == 0;
}
[–] Sanctus@lemmy.world 29 points 1 month ago (1 children)

Anything but using modulo I guess

[–] lnxtx@feddit.nl 6 points 1 month ago

And bit operations (:

[–] YtA4QCam2A9j7EfTgHrH@infosec.pub 14 points 1 month ago (1 children)

This makes me happy that I don’t use genai

[–] Mirodir@discuss.tchncs.de 7 points 1 month ago

I'm not sure how fucked up their prompt is (or how unlucky they were). I just did 3 tries and every time it used modulo.

I'm assuming they asked it specifically to either not use modulo or to do a suboptimal way to make this joke.

[–] affiliate@lemmy.world 22 points 1 month ago (1 children)

a wise programmer knows to always ask the question "can i solve this problem in python using metaprogramming?" in this instance, the answer is yes:

def is_even(n: int):
    s = "def is_even_helper(number: int):\n"
    b = True
    for i in range(0, abs(n)+2):
        s += f"\tif (abs(number) == {i}): return {b}\n"
        b = not b
    exec(s)
    return locals().get("is_even_helper")(n)
[–] sepiroth154@feddit.nl 7 points 1 month ago

Gotta love how human readable Python always is!

[–] istdaslol 18 points 1 month ago (1 children)

When you sacrifice memory for an O(1) algorithm.

In this case still O(n)

[–] Zangoose@lemmy.world 6 points 1 month ago

Smh this is literally what switch statements are for

[–] TunaCowboy@lemmy.world 15 points 1 month ago (1 children)
[–] FiskFisk33@startrek.website 4 points 1 month ago

if (~number & 1)

[–] dadarobot@lemmy.sdf.org 15 points 1 month ago (2 children)
If number%2 == 0: return("Even")
Else: return("odd") 
[–] istdaslol 4 points 1 month ago

Not all ARM CPUs support mod operations. It’s better to use bit operations. Check if the last bit is set. If set it’s odd else it’s even.

load more comments (1 replies)
[–] FiskFisk33@startrek.website 14 points 1 month ago (4 children)

oh of course there is

https://www.npmjs.com/package/is-even

(do take a look at the download stats)

[–] FJW@discuss.tchncs.de 13 points 1 month ago* (last edited 1 month ago)

And that isn’t even the worst thing about it…

The implementation looks like this:

function isEven(i) {
  return !isOdd(i);
};

And yes, is-odd is a dependency that in turn depends on is-number

[–] servobobo@feddit.nl 7 points 1 month ago* (last edited 1 month ago)

"If it's not an npm package it's impossible"

- JS devs, probably

[–] Micromot 7 points 1 month ago* (last edited 1 month ago) (4 children)

Can't you just

If (number % 2 == 0){return true}

[–] blackn1ght@feddit.uk 12 points 1 month ago (1 children)
load more comments (1 replies)
[–] drake@lemmy.sdf.org 6 points 1 month ago (3 children)

but what if number isn’t an integer, or even a number at all? This code, and the improved code shared by the other user, could cause major problems under those conditions. Really, what you would want, is to validate that number is actually an integer before performing the modulo, and if it isn’t, you want to throw an exception, because something has gone wrong.

That’s exactly what that NPM module does. And this is why it’s not a bad thing to use packages/modules for even very simple tasks, because they help to prevent us from making silly mistakes.

load more comments (3 replies)
[–] FiskFisk33@startrek.website 5 points 1 month ago

yup, which is why I find the download stats truly horrifying

[–] tb_@lemmy.world 5 points 1 month ago

That's a lot of downloads

[–] ashestoashes@lemmy.blahaj.zone 10 points 1 month ago

just check the least significant bit smh my head

[–] moistclump@lemmy.world 6 points 1 month ago

I thought they were going to turn into Saddam Husseins.

load more comments
view more: next ›