Addition without Addition

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Addition without Addition

Timothy Foster 17 Jun 2018 02:49

Here's a code golf challenge to poke ya'll brains a little. The goal is to write the smallest program possible that accomplishes the goal. There's no prize; it's just a fun exercise!

Write a program that adds two integers together without the use of +, -, sum, or cumSum.

• The program may not use the + or - operators.
• The program may not use the sum command or cumSum command.
• Assume the first line of your program is :Prompt A,B
• A and B are both integers whose absolute values are no more than 99
• You may assume A and B are strictly positive

For a bonus challenge, try writing the same program, except this time A and B are not restricted to the set of positive integers, meaning negative values are allowed.

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Last edited on 17 Jun 2018 03:13 by Timothy Foster Show more

Re: Addition without Addition

Trenly 17 Jun 2018 02:57

Easy:

Prompt A,B
sum({A,B

Re: Addition without Addition

Timothy Foster 17 Jun 2018 03:02

I forgot about the sum command ( :

Now try it without that.

EDIT: Also without cumSum, because that's basically the same thing.

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Last edited on 17 Jun 2018 03:13 by Timothy Foster Show more

Re: Addition without Addition

lirtosiast 11 Sep 2018 22:07

2mean(A,B?

Re: Addition without Addition

Michael2_3B 11 Sep 2018 23:06

Or 2median({A,B

Re: Addition without Addition

kg583 17 Jun 2018 03:04

I feel like this was supposed to be more difficult:

Show Code

:Prompt A,B
:log(10^(A)10^(B

Should work for -99 ≤ A + B ≤ 99 (so I guess it technically doesn't meet the criteria for A or B being up to 99 but it does allow for negatives)

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The solution to a complex problem is often a simple answer.

Re: Addition without Addition

Timothy Foster 17 Jun 2018 03:10

It's not meant to be that hard, but I'd like to encourage the community to put forth more exercises like these.

How would you modify the code to handle the 99+99 case?

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Re: Addition without Addition

kg583 17 Jun 2018 03:48

Use a logarithm with a smaller base:

Show Code

:Prompt A,B
:logBASE(2^A2^B,2

A+B can be as large as 332 (or as small as -332)

You could theoretically lower the base further to just bigger than 1 for a wider range though at that point I'd imagine you'd run into accuracy problems.

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The solution to a complex problem is often a simple answer.

Last edited on 17 Jun 2018 03:51 by kg583 Show more

Re: Addition without Addition

Trenly 17 Jun 2018 04:06

True, but logBASE( is only available on the 84+SE with OS 2.53 MP or higher

For the 83+ you would have to use ln(

Show Code

Prompt A,B
ln(e^(A)e^(B)

--or--

Prompt A,B
ln(1.0001^A(1.0001^B))/ln(1.0001)

Last edited on 17 Jun 2018 04:09 by Trenly Show more

Re: Addition without Addition

(account deleted) 22 Jun 2018 16:42

What about the plain TI-84 Plus? It's on mine. XD

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Hewwo, my name is Achak Claw. I was formerly BioHazard.

Re: Addition without Addition

Trenly 22 Jun 2018 17:26

Yeah, but its not on the 83

Re: Addition without Addition

Xeda Elnara 05 Aug 2018 01:51

This is 10 bytes and works on any non-negative number as long as A+B would not cause overflow.

R▶Pr(√(A),√(B))²

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Z80 Assembly>English>TI-BASIC>Python>French>C>0

Last edited on 05 Aug 2018 01:51 by Xeda Elnara Show more

Re: Addition without Addition

Yousername 10 Nov 2020 20:56

Prompt A,B
∆List({~A,B
Ans(1

(where "~" is the negative sign)

Re: Addition without Addition

(account deleted) 10 Nov 2020 21:51

This forum thread is over two years old, I doubt Timothy Foster is looking for a solution to this challenge.

If you want, you can make a new thread and reference this one.

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Hewwo, my name is Achak Claw. I was formerly BioHazard.