Problem 1774. Free passes for everyone!

Created by Alfonso Nieto-Castanon

Solve Later

{"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","targetMode":"","relationshipId":"rId1","target":"/matlab/document.xml"},{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/output","targetMode":"","relationshipId":"rId2","target":"/matlab/output.xml"}],"parts":[{"partUri":"/matlab/document.xml","relationship":[],"contentType":"application/vnd.mathworks.matlab.code.document+xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\"><w:body><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:rPr><w:i/></w:rPr><w:t>Simply return the name of the coolest numerical computation software ever</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:rPr><w:b/></w:rPr><w:t>Extra reward</w:t></w:r><w:r><w:t> (get a</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>freepass</w:t></w:r><w:r><w:t>):</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Once a month, as an additional reward for solving this problem, you may get a temporary freepass</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:b/></w:rPr><w:t>to solve any other Cody problem</w:t></w:r><w:r><w:t>. To use this freepass follow these steps:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"ListParagraph\"/><w:numPr><w:numId w:val=\"2\"/></w:numPr></w:pPr><w:r><w:t>First, at the beginning of a new month, solve this problem correctly</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"ListParagraph\"/><w:numPr><w:numId w:val=\"2\"/></w:numPr></w:pPr><w:r><w:t>Then immediately visit the Cody problem that you wish to solve, click 'Solve this now', and enter within the function body of your solution the line:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[ freepass.please;]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>and Cody</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>may</w:t></w:r><w:r><w:t> accept that solution as correct.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>You will typically need to repeat step (2) above multiple times until Cody</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>does</w:t></w:r><w:r><w:t> accept your solution as correct. If you are getting an error message saying</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>Undefined variable \"freepass\" or class \"freepass.please\"</w:t></w:r><w:r><w:t> simply continue repeating step 2 until you pass the problem and get a message saying</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>freepass granted, congratulations!</w:t></w:r><w:r><w:t>.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:rPr><w:b/></w:rPr><w:t>Fineprint</w:t></w:r><w:r><w:t>:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>1) For each Cody player, this problem will grant a new freepass per day until one is successfully used to pass a different Cody problem. Once this happens this problem will only grant the same Cody player a new freepass the next Calendar month.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>2)</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>How many times do I need to submit a freepass.please solution to a different Cody problem for it to pass?</w:t></w:r><w:r><w:t> Short answer: around 10, but perhaps as many as 30 times (your faith may be tested, but perseverance will be rewarded at the end :)</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Long answer: at any given time, Cody has many servers running players' solutions (perhaps around 20 servers?). Every time that you solve this problem a</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>freepass</w:t></w:r><w:r><w:t> is issued only for the particular server where your solution was evaluated. When you run a</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>freepass.please</w:t></w:r><w:r><w:t> solution, if that solution is run in the same server where a freepass was issued your solution will pass, otherwise you will get an \"_undefined variable freepass_\" error. So in order for your solution to pass you simply need to keep resubmitting it until you finally hit the same server where your freepass-problem solution was originally evaluated. Also note that, from time to time, Cody will close a server and start a new one. If that happens any freepass stored in that server will be lost (and you will need to try again steps 1 and 2 above next day)</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>3) Your correct solution will get a score of 100 (this is typically high enough so that we do not troll the score lead with these freepasses)</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>4) Feel free to explore this problem testsuite to see how this works, but please respect some basic courtesy guidelines if you decide to implement your own (e.g. the service does not interfere with the normal Cody operation; it cleans up after itself; don't use it to get a leading score; etc.) Comments and suggestions for improvement are appreciated!</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>5) This</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>freepass</w:t></w:r><w:r><w:t> service is 'likeware'. Please 'like' this problem if you liked the code or enjoy using your freepasses :)</w:t></w:r></w:p></w:body></w:document>"},{"partUri":"/matlab/output.xml","contentType":"text/xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?><embeddedOutputs><metaData><evaluationState>manual</evaluationState><layoutState>code</layoutState><outputStatus>ready</outputStatus></metaData><outputArray type=\"array\"/><regionArray type=\"array\"/></embeddedOutputs>"}]}

Simply return the name of the coolest numerical computation software everExtra reward (get a freepass):Once a month, as an additional reward for solving this problem, you may get a temporary freepass to solve any other Cody problem. To use this freepass follow these steps:<ol><li>First, at the beginning of a new month, solve this problem correctly</li><li>Then immediately visit the Cody problem that you wish to solve, click 'Solve this now', and enter within the function body of your solution the line:</li></ol><pre> freepass.please;</pre>and Cody may accept that solution as correct.You will typically need to repeat step (2) above multiple times until Cody does accept your solution as correct. If you are getting an error message saying Undefined variable "freepass" or class "freepass.please" simply continue repeating step 2 until you pass the problem and get a message saying freepass granted, congratulations!.Fineprint:1) For each Cody player, this problem will grant a new freepass per day until one is successfully used to pass a different Cody problem. Once this happens this problem will only grant the same Cody player a new freepass the next Calendar month.2) How many times do I need to submit a freepass.please solution to a different Cody problem for it to pass? Short answer: around 10, but perhaps as many as 30 times (your faith may be tested, but perseverance will be rewarded at the end :)Long answer: at any given time, Cody has many servers running players' solutions (perhaps around 20 servers?). Every time that you solve this problem a freepass is issued only for the particular server where your solution was evaluated. When you run a freepass.please solution, if that solution is run in the same server where a freepass was issued your solution will pass, otherwise you will get an "_undefined variable freepass_" error. So in order for your solution to pass you simply need to keep resubmitting it until you finally hit the same server where your freepass-problem solution was originally evaluated. Also note that, from time to time, Cody will close a server and start a new one. If that happens any freepass stored in that server will be lost (and you will need to try again steps 1 and 2 above next day)3) Your correct solution will get a score of 100 (this is typically high enough so that we do not troll the score lead with these freepasses)4) Feel free to explore this problem testsuite to see how this works, but please respect some basic courtesy guidelines if you decide to implement your own (e.g. the service does not interfere with the normal Cody operation; it cleans up after itself; don't use it to get a leading score; etc.) Comments and suggestions for improvement are appreciated!5) This freepass service is 'likeware'. Please 'like' this problem if you liked the code or enjoy using your freepasses :)

Solve

Solution Stats

3425 Solutions
629 Solvers

Last Solution submitted on Dec 02, 2020

Last 200 Solutions

Problem Comments

20 Comments

20 Comments

Show 17 older comments

Claudio Gelmi on 6 Aug 2013

Alfonso, it is incredibly clever and ingenious!!!

Alfonso Nieto-Castanon on 7 Aug 2013

Thanks!

Chintan on 13 Aug 2013

Amazing, it works. Very Clever.

Christopher on 13 Nov 2013

Finally! I can now beat the cody problem that wants me to play on the weekend. Smart and subversive. My new favorite cody problem.

Dimitrios on 8 Mar 2014

nice!

Jonathan Campelli on 29 Apr 2015

If I had read 3) more carefully, I would not have used to solve the Rubik's Cube problem like I did. My apologies.

Alicia Aliaga Vicente on 13 May 2015

Nice!

Alfonso Nieto-Castanon on 19 Jun 2015

Freepass functionality has not been working for the past few weeks due to a change in the underlying Cody machinery. The fix to get freepasses working again is very simple but I am hesitant whether I should take this change in Cody machinery as a sign from above and let this problem quietly expire. If you believe freepasses are useful please let me know in the comments, and if you believe they interfere too much with the normal Cody balance and I should let this functionality expire please let me know as well. Other thoughts/suggestions are also welcome (I could implement a maximum number of freepasses per user per week, for example, if that would help avoid abuses)

goc3 on 14 Aug 2015

I would prefer that it be kept up, if possible, with a limiter, like you mentioned, of one or two per user per week. The reasoning is there are many problems on Cody which can no longer be solved (some older ones, due to Matlab or Cody upgrades) or which were never solvable without hacking due to poorly written test suites. Since these problems typically aren't removed from Cody, newer players shouldn't be handicapped by never being able to solve all posted problems.

James on 14 Aug 2015

Can you get this working on the Simulink problems? :-)

Alfonso Nieto-Castanon on 27 Jan 2016

just an update: it would seem that Cody has now perhaps between 30 and 50 nodes/servers instead of the old ~5 nodes running Cody solutions. This just means that you need more patience/persistence to get a freepass. The recommended "optimal" balance would now be to send ~7 correct solutions to this problem, and then submit freepass.please solutions to your secondary problem until you hit the right server and get a passing grade (on average you would need another ~7 freepass.please submissions until you hit the right server). I will update this post if I get a better estimate on the actual number of servers running cody solutions

goc3 on 1 Sep 2016

Cody has had some improvements recently, and it appears that this no longer works. The function will sometimes return successfully, but I can't get more than four in a row. The error description is: "No public property version exists for class cody.verifyCode." Is this problem now dead, or can it be revived, perhaps with a maximum per user per time period as mentioned in other comments here?

goc3 on 1 Sep 2016

And, better yet, I now get that cody.verifyCode class error randomly when trying to solve other problems.

Jan Orwat on 1 Sep 2016

Hi Grant. Many users reported cody.verifyCode problems in comments. In the last couple of days I've got it about 10% of the submissions. I guess it's independent from free pass problem.

Alfonso Nieto-Castanon on 1 Sep 2016

@Grant/Jan. This could still be related so just to play it safe I am temporally taking this problem down until I can have it fixed/updated

Dan Po on 24 Sep 2016

does this hack still work?

mohd mu'aazullah yaakob on 28 Dec 2016

Nice one

Yusra Ashfaq on 28 Dec 2016

Matthew Luerman on 4 Aug 2017

lol

Alfonso Nieto-Castanon on 28 Oct 2017

this problem is working again

Solution Comments

Solution 1352215

2 Comments

2 Comments

Michael Eldredge on 21 Nov 2017

I don't get it. I am doing these things for fun. How is not doing a problem a reward?

Alfonso Nieto-Castanon on 21 Nov 2017

scenario #1: you run into a problem that you really like but no matter how hard you try you do not seem to be able to figure out how to solve it. You are ready to "give up" but would *really really really* like to see other players' solutions and learn from them. Unfortunately Cody does not let you see other people's solutions until you provide one of your own. A freepass allows you to bypass this restriction (from time to time and with a little effort from your side so it does not break the logic/motivation of the game)

Solution 700831

1 Comment

1 Comment

Sreenath Sivadas on 14 Jul 2015

cool..
:P

Problem Recent Solvers629

Problem Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Problem 1774. Free passes for everyone!

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers629

Suggested Problems

More from this Author38

Problem Tags

Community Treasure Hunt

Problem 1774. Free passes for everyone!

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers629

Suggested Problems

More from this Author38

Problem Tags

Community Treasure Hunt

Players