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WEEKLY CHALLENGES #1
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TheDrone7 (1034)

Hello all replers! Today, I'm going to be announcing something new and fun for you all. We're introducing WEEKLY CHALLENGES!.

So, what are these weekly challenges? These are small beginner-friendly programming problems for the community to solve. We will be posting one of these every week. After 1 week of posting the challenge, we'll stop accepting any answers for the current challenge and post a new one, (although, you can still solve these for fun or just to learn something new).

And, what's in it for me? We will grade your submissions for each challenge you attempt. By the end of the month, the person to have the highest total score will be awarded 1 month of free hacker plan!!

HOW DO I SUBMIT? You can submit your answers by sharing the repls to the share board of repl talk and ensure that the name of the post contains #WEEKLY (in all caps, this will help us filter your submissions).

Now that all the introductions are done, let's get to the point, i.e. this week's weekly challenge!


Multiplication!


For this week's weekly challenge, you will need to write a program that multiplies 2 numbers. BUT, there's a twist. You are NOT ALLOWED to use the multiplication operator (*) or loops(for, while or any other that your prefered language may support, goto also counts as a loop). You cannot use any external libraries and anything else is allowed.

QUICK NOTE : Since these challenges are very easy, this should be obvious but we will not only be judging your output but also your code. The actual marking scheme will remain hidden though.

Commentshotnewtop
KobeFF (346)

In LOLCODE can you use the PRODUCKT function?

yummypasta (2)

Here's my esoteric solution, leveraging the fact that for any number a in base b, a << 1 (append a 0 to the end) is a * b.

Note: Only works if 2 <= b <= 36, and both a and b is an integer.

parseInt(
    a.toString(b) + '0',
    b
);
AgastyaSandhuja (146)

can you use a module where you can just do

mathmodule.multiply(a,b)
IceWolfy1 (5)

@AgastyaSandhuja i would assume no becouse in that it uses the * but i could be wrong

TheDrone7 (1034)

NO @AgastyaSandhuja there should be no use of any multiplication operator or loops or external modules.

PDanielY (978)

What if you already have hacker plan? Will they change the expiring date of the hacker plan?

HahaYes (1014)

@PDanielY They will probably wait for it to expire then give you an extra month

dotcomboom (93)
x = 69
y = 420
z = round(x / (1 / y))
print(z)

dude python lmao

eric_wang (10)

@dotcomboom you might need to count for the zerodivisionerror edge case, in the event that y is 0.

dotcomboom (93)

@eric_wang Good point, here's my updated version:

def multiply(x, y):
	if y == 0:
		return 0
	return round(x / (1 / y))
print(multiply(69, 420))
Lord_Poseidon (158)

do recursive functions count as loops?

Lord_Poseidon (158)

@TheDrone7 YEET. I already cooked up a dumb method involving map, strings, lists and binary arithmetic. Are multiple submissions allowed?

TheDrone7 (1034)

No @Lord_Poseidon only submit the one you think will score the most.

Lord_Poseidon (158)

without even knowing how code is judged? This is sad :(

AtriDey (104)

Can I use automation plugins? Not a math plugin, but a mouse mover.

Coder100 (4007)

lol what do you need a mouse for XD
pyautogui doesn't work on repl.it :( @AtriDey

AtriDey (104)

@Coder100 autopy works without a hitch.

ThatSmart (86)

if i do it in brainf can i use loops

AtriDey (104)

So there can be no loops in a code file (py, cpp, js, etc)
And does the math have to be done in the program?
CMON CODEMONKEY TOOK MY IDEA I NEED A LOOPHOLE NOW!

NoelB33 (308)

Well, he never said it has to be done in a code file... @AtriDey

ABDOABDO11 (1)

const multiply=require("multiplier");
function multiple(num1, num2){
return multiply(num1, num2);

}
console.log(multiple(5, 5))

ChezCoder (1479)

will python chr() and eval() work?

eartharoid (0)

https://repl.it/@eartharoid/WEEKLY-1
not sure if an interval counts as a loop
probably a terrible way to do it, but it works. :)

DynamicSquid (2611)

Quick question, can I use for_each()? Not to multiply the number directly, but it's for a list

DynamicSquid (2611)

Wait, so I can still use #include <something>, right?

AtriDey (104)

@DynamicSquid I haven't touched C++ in a while, but I think header files count as external libraries. Idk, it's up to @TheDrone7.

DynamicSquid (2611)

@AtriDey but like, i'm assuming we can use iostream, so I think @TheDrone7 is referring to things withing the standard namespace

AtriDey (104)

@DynamicSquid Yeah, no iostream is sorta harsh. Since stdio.h is also a header, I guess some exceptions have to be made. I guess we wait for @TheDrone7.

AmazingMech2418 (691)

@DynamicSquid iostream and iomanip should be allowed (or in C, stdio and stdlib), but I think others that add functionality to the language that is not required (sorry, I think maybe even vector) are not allowed.

TheDrone7 (1034)

You can use any modules from the standard library of the language, just not external modules that don't come built in with the language. @AmazingMech2418

TheDrone7 (1034)

Standard library is totally fine. @AtriDey

BenjaminUrquhar (14)

Everyone's doing double division. Be more creative smh.

CodingCactus (2750)

@BenjaminUrquhar it's the fastest way to solve the problem, would you ever want a slow function in your program if you can have a fast one that does the same thing?

AdCharity (1270)

@BenjaminUrquhar smh but in ruby you can divide by zero so it's perfect

BenjaminUrquhar (14)

@CodingCactus I'm not going for efficiency. If I was I'd just use the multiplication operator directly.

AmazingMech2418 (691)

@BenjaminUrquhar I personally prefer string-based math for this one...

bramley (194)

sounds fun epic ngl

Scoder12 (640)

Awesome free hacker plan here I come

eankeen (1222)

are multiple submissions valid? @TheDrone7

PYer (3290)

same. I have 3 ideas already... @eankeen

TheDrone7 (1034)

No @eankeen. You may only make one submission. Submit the one you think will score the highest ;)