Problem 44348. Seemingly impossible problem

Created by David Verrelli

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:t>This is a</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>seemingly</w:t></w:r><w:r><w:t> 'impossible' problem, because variously your function, \"impossibleFn\", must return an output of either 1 or 2 or 3 for the same input (0, the number zero). Why is this described as \"seemingly impossible\"? Because it does not satisfy the</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>mathematical</w:t></w:r><w:r><w:t> definition of a function. Yet there is still</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>at least</w:t></w:r><w:r><w:t> one way to pass all the tests! (One simple code has been verified to work. However, all's fair in this problem, so try whichever hacks and workarounds are at your disposal.) UPDATE: Now</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:i/></w:rPr><w:t>more than three</w:t></w:r><w:r><w:t> (unrelated) approaches have been verified to pass all the tests.</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>"}]}

Solve

Solution Stats

275 Solutions
23 Solvers

Last Solution submitted on Oct 26, 2020

Last 200 Solutions

Problem Comments

2 Comments

2 Comments

Jean-Marie Sainthillier on 9 Mar 2018

Add more tests, for example:
Test1 : 0->1
Test2: 1->1
Test3: 0->2
Test4: 6->6
Test 6: 0->0
...

David Verrelli on 10 Mar 2018

Hello, Jean-Marie Sainthillier. Thanks for the suggestion. If I understand you correctly, that could be done, but it would break all/most of the previous submissions, so it seems better to do that in a separate problem — if you would like to make one. —DIV

Solution Comments

Solution 1281486

2 Comments

2 Comments

Jean-Marie Sainthillier on 14 Mar 2018

You should try the timer function.

David Verrelli on 15 Mar 2018

Nice thought. I _eventually_ got that to work (Solution 1463623), but it also seems a bit clunky in the end, and it completely fails if implemented without an additional explicit instruction that ensures control is not returned to the "command prompt" (and hence the Test Suite!) until after the specified timer period has elapsed.

Solution 1277200

2 Comments

2 Comments

James on 27 Sep 2017

Would this also work if the y_correct values were 3, 2, 1 instead of 1, 2, 3?

David Verrelli on 28 Sep 2017

The code _as is_ wouldn't work, but it could easily be adapted. Either with a switch statement, or by simply calculating 4 – {erstwhile result};

Problem Recent Solvers23

Problem Tags

hack impossible

Community Treasure Hunt

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

Start Hunting!

Problem 44348. Seemingly impossible problem

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers23

Suggested Problems

More from this Author31

Problem Tags

Community Treasure Hunt

Problem 44348. Seemingly impossible problem

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers23

Suggested Problems

More from this Author31

Problem Tags

Community Treasure Hunt

Players