Problem 2825. pay it forward

Created by Alfonso Nieto-Castanon

Solve Later

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Choose a number (integer between 0 and 65535)You will pass this problem if you are the second person to choose that same numberGood luck!How it worksYour function should simply return the number you have chosen. Your solution will always get a score equal to the number you choose (independently of whether the solution passes the test or fails). Your solution will pass the test iff:1. there is one (and only one) other solution that has obtained the same score as yoursand 2. this previous solution had been created by a different Cody player (it was not crafted by yourself)Typically this previous solution (from someone else) would be a failed submission (and that is perfectly fine), since at that time it would have been the first solution submitted to get that score. See the testsuite for details.NotesTypically you will need to cooperate with other Cody players, or depend on their kindness, to be able to solve this problem.If you prefer to go the 'solo' route any number of hacking solutions would also work (but they are not the intended focus of this particular problem)

Choose a number (integer between 0 and 65535)

You will pass this problem if you are the *second* person to choose that same number

Good luck!

*How it works*

Your function should simply return the number you have chosen. Your solution will always get a score equal to the number you choose (independently of whether the solution passes the test or fails). Your solution will pass the test iff:

1. there is one (and only one) other solution that has obtained the same score as yours

and 2. this previous solution had been created by a different Cody player (it was not crafted by yourself)

Typically this previous solution (from someone else) would be a failed submission (and that is perfectly fine), since at that time it would have been the first solution submitted to get that score. See the testsuite for details.

*Notes*

Typically you will need to cooperate with other Cody players, or depend on their kindness, to be able to solve this problem.

If you prefer to go the 'solo' route any number of hacking solutions would also work (but they are not the intended focus of this particular problem)

Solve

Solution Stats

310 Solutions
34 Solvers

Last Solution submitted on Oct 25, 2022

Last 200 Solutions

Problem Comments

9 Comments

9 Comments

Show 6 older comments

Alfonso Nieto-Castanon on 11 Jan 2015

If you are the first player to attempt this problem, I left number 42 open for you. Cheers!

Mattias on 11 Jan 2015

Very creative problem! Took me a while to understand the test code and then realized I had the golden opportunity. And "paid it forward" too

James on 12 Jan 2015

Whoever you are, I have always depended on the kindness of strangers.

Alfonso Nieto-Castanon on 19 Jun 2015

Sorry for the discontinuity. This problem is working again (changes in Cody were interfering with our old way of assigning not-size-based scores to solutions). Let me know if you still run into any issues.

Alfonso Nieto-Castanon on 19 Jun 2015

note: as a side effect of the glitch solutions submitted between May and June 2015 had been incorrectly scored so please disregard those

Rafael S.T. Vieira on 27 Sep 2020

It is possible to solve this problem without relying on the kindness of strangers or hacking. Just think...

Alfonso Nieto-Castanon on 27 Sep 2020

@Rafael: thanks for you comment, and I guess you are right and kindness is in the eye of the beholder, but for example I see your solution using y=10 relying on Jonathan's kindness (as he submitted that 10 before you did), and similarly I see your failed -but kind!- y=50382 solution hopefully helping some other player solve this problem in the future, effectively paying that kindness forward (thanks!). That said, perhaps Jonathan, or you, were not really trying to be kind to others with their failed solution attempts and were instead just trying out some random solutions, but hey, I like my interpretation better :)

Rafael S.T. Vieira on 29 Sep 2020

Everyone is entitled to an opinion, Alfonso :), but I went with Benford's Law and code analysis.

Nikolaos Nikolaou on 22 Oct 2020

and i went with Alfonsos kind lengthy comment :)

Solution Comments

Solution 1321073

1 Comment

1 Comment

David Verrelli on 28 Feb 2018

I did not expect that this Solution would pass. . . . Solution 556171 was submitted on 12 Jan 2015 with Size = 65535 by unknown Player (first instance, so marked as incorrect).
Solution 557603 was submitted on 14 Jan 2015 with Size = 65535 by Michael C. (second instance, so marked as correct).
Solution 828081 was submitted on 15 Feb 2016 with Size = 65535 by unknown Player (third instance, so marked as incorrect). . . . So this here would be the fourth instance, no?

Solution 1283190

3 Comments

3 Comments

David Verrelli on 9 Oct 2017

Is this Test still working? I submitted a problem of size 100, and also returned the number 100 from the function, and AFAIK there was only one other solution with this score previously submitted (and which wasn't submitted by me), namely https://www.mathworks.com/matlabcentral/cody/problems/2825-pay-it-forward/solutions/556177 . Admittedly that supposedly needs rescoring, but I didn't think that should affect anything.

James on 27 Feb 2018

I just got the heads up that my original solution to this problem had been nullified when this problem showed up on my "not solved" listing. Out of curiosity, I entered 100 as my entry, and it told me that there were two other entries with that number. If I understand the suite correctly, and it's still working as it should, your "100" solution should probably have worked, David.

David Verrelli on 28 Feb 2018

Hi, James. Actually, this Solution (my "100" Solution) was initially marked as 'incorrect', but a while after my Comment was posted the Solution was remarked to 'correct'. I surmise that Alfonso Nieto-Castanon updated the Test Suite to account for some changes to how Cody works. Although he has not made a Comment to that effect, besides the changed scoring of my Solution it is notable that A. N.-C. also submitted a (correct) Solution on 30 Oct 2017, which I would interpret as a validation exercise by the Problem's creator. So it seems a glitch arose some time after the Problem's inception, and that glitch was fixed in mid/late October 2017. —DIV

Solution 566247

1 Comment

1 Comment

J.R.! Menzinger on 27 Jan 2015

Without clicking on the "Solve it now" button I though 42, then I saw your proposal...
so I choose 43 (Meeeeeeeec!)
my second try was this!
BINGOOOO!!

Solution 557526

1 Comment

1 Comment

Michael Ryan on 14 Jan 2015

A few primes for people...

Solution 556207

1 Comment

1 Comment

James on 12 Jan 2015

Please don't rescore this one, as I matched it. :-)

Solution 555376

2 Comments

2 Comments

rifat on 11 Jan 2015

at last understood it. And, helped someone get a zero score

Mattias on 11 Jan 2015

Thank you for this ;)

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Problem 2825. pay it forward

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Problem 2825. pay it forward

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