Problem 42705. Is It a Snake?

Created by Ned Gulley

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>Given an m-by-n matrix, return true if the elements of the matrix are a connected \"snake\" shape from 1 to m*n. Otherwise return false.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Snakes are vectors that move through the grid of a matrix in a 4-connected sense. So the number 1 can be anywhere, but the number 2 must be north, south, east, or west of 1. And the number 3 must be north, south, east, or west of 2. And so on.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Examples</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"code\"/></w:pPr><w:r><w:t><![CDATA[ [ 1 2 3 4 5 ]    is a snake\n\n [ 2 1 3 4 ]      is NOT a snake\n\n [ 1 2 3 2 1 ]    is NOT a snake\n\n [ 6 5 4 3 ]      is NOT a snake\n\n [ 6 1 2 \n   5 4 3 ]        is a snake\n\n [ 1 2\n   3 4 ]          is NOT a snake\n\n [  7  8  9 10\n    6  1  2 11\n    5  4  3 12\n   16 15 14 13 ]  is a snake]]></w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>NOTE: Answers to this problem helped me write the test suite for Cody Problem 42708,</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"https://www.mathworks.com/matlabcentral/cody/problems/42708-placing-beads-neatly-in-a-box\"><w:r><w:t>Placing Beads Neatly in a Box</w:t></w:r></w:hyperlink><w:r><w:t>. Thanks!</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

137 Solutions
31 Solvers

Last Solution submitted on Jun 30, 2020

Last 200 Solutions

Problem Comments

Solution Comments

Solution 814324

1 Comment

1 Comment

Peng Liu on 26 Jan 2016

Similar to Solution Solution 814072, this solution would fail a test with a = [2 1 1 1].

Solution 814072

2 Comments

2 Comments

Alfonso Nieto-Castanon on 26 Jan 2016

this solution would fail a test of the form a=[2 1 1 1];

Ned Gulley on 27 Jan 2016

I added [2 1 1 1] as a test.

Solution 804605

3 Comments

3 Comments

Brian Hannan on 18 Jan 2016

This solution passes the test suite when I run it on my machine. Does anyone know why it would fail when I submit it to Cody? The online test suite shows only red X marks and does not provide any feedback.

Jan Orwat on 19 Jan 2016

"padarray" comes from Image Processing Toolbox

Brian Hannan on 20 Jan 2016

Thanks.

Problem Recent Solvers31

Problem Tags

badger badger badger badger matrix manipulation

Community Treasure Hunt

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

Start Hunting!

Problem 42705. Is It a Snake?

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers31

Suggested Problems

More from this Author50

Problem Tags

Community Treasure Hunt

Problem 42705. Is It a Snake?

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers31

Suggested Problems

More from this Author50

Problem Tags

Community Treasure Hunt

Players