Problem 42782. GJam March 2016 IOW: Passwords and the Block Set

Created by Richard Zapor

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 Challenge is derived from</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"http://code.google.com/codejam/contest/8274486/dashboard#s=p3\"><w:r><w:t>GJam March 2016 Annual I/O for Password Security</w:t></w:r></w:hyperlink><w:r><w:t>. This is the small-2 case of up to 50 passwords of length 1 to 26</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>The GJam story goes that a random block set A:Z exists to the child of a paranoid corporate president. He is worried that his password(s) may exist in the block pattern. Produce a 26 character block sequence that does not contain his password. If no sequence can be made that does not contain his strong password output 'IMPOSSIBLE'.</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>Input:</w:t></w:r><w:r><w:t> [PW], string up to 50 space separated passwords of 1 to 26 characters</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>Output:</w:t></w:r><w:r><w:t> [Pstr], string containing A:Z with no instance of PW or 'IMPOSSIBLE'</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>Examples:</w:t></w:r><w:r><w:t> [PW] [Pstr]</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[[X] [IMPOSSIBLE] \n[QQ][ABCDEFGHIJKLMNOPQRSTUVWXYZ]\n['XYZ GCJ OMG LMAO JK'][ABCDEFGHIKLMNOPQRSTUVWXYJZ]]]></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></w:t></w:r><w:hyperlink w:docLocation=\"http://code.google.com/codejam\"><w:r><w:rPr><w:b/></w:rPr><w:t>Google Code Jam 2016 Open Qualifier: April 8, 2016</w:t></w:r></w:hyperlink></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:rPr><w:b/></w:rPr><w:t>Theory:</w:t></w:r><w:r><w:t> Remove Impossible cases first. Produce a PW string with a robust start/end pairs and a random middle. Try multiple formats with a timer. The most common letter can be placed at both the start and end with random internal letters. OR you can just guess for awhile and then give up. The key here is an efficient invalid string check. The IOW Champion Stacy992's java solution is in the test suite for misguidance versus the Matlab 5 line solution.</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>"}]}

This Challenge is derived from <a href = "http://code.google.com/codejam/contest/8274486/dashboard#s=p3">GJam March 2016 Annual I/O for Password Security</a>. This is the small-2 case of up to 50 passwords of length 1 to 26The GJam story goes that a random block set A:Z exists to the child of a paranoid corporate president. He is worried that his password(s) may exist in the block pattern. Produce a 26 character block sequence that does not contain his password. If no sequence can be made that does not contain his strong password output 'IMPOSSIBLE'.Input: [PW], string up to 50 space separated passwords of 1 to 26 charactersOutput: [Pstr], string containing A:Z with no instance of PW or 'IMPOSSIBLE'Examples: [PW] [Pstr]<pre class="language-matlab">[X] [IMPOSSIBLE] 
[QQ][ABCDEFGHIJKLMNOPQRSTUVWXYZ]
['XYZ GCJ OMG LMAO JK'][ABCDEFGHIKLMNOPQRSTUVWXYJZ] 
</pre><a href = "http://code.google.com/codejam">Google Code Jam 2016 Open Qualifier: April 8, 2016</a>Theory: Remove Impossible cases first. Produce a PW string with a robust start/end pairs and a random middle. Try multiple formats with a timer. The most common letter can be placed at both the start and end with random internal letters. OR you can just guess for awhile and then give up. The key here is an efficient invalid string check. The IOW Champion Stacy992's java solution is in the test suite for misguidance versus the Matlab 5 line solution.

Solve

Solution Stats

9 Solutions
5 Solvers

Last Solution submitted on Aug 20, 2019

Last 200 Solutions

Problem Recent Solvers5

Problem Tags

contest gjam randperm stable strsplit unique

Community Treasure Hunt

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

Start Hunting!

Problem 42782. GJam March 2016 IOW: Passwords and the Block Set

Solution Stats

Last 200 Solutions

Problem Recent Solvers5

Suggested Problems

More from this Author247

Problem Tags

Community Treasure Hunt

Problem 42782. GJam March 2016 IOW: Passwords and the Block Set

Solution Stats

Last 200 Solutions

Problem Recent Solvers5

Suggested Problems

More from this Author247

Problem Tags

Community Treasure Hunt

Players