Problem 42749. Find the nearest prime

Created by Pooja Narayan

Solve Later

{"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","relationshipId":"rId1","target":"/matlab/document.xml"},{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/output","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\"?><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 a positive integer 'n', the task is to find a prime number greater than or equal to 'n'.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>Example 1</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>If given 'n' is 10, then the closest prime number greater than 10 is 11 at a distance of 1. So 11 must be returned.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>Example 2</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>If the given 'n' is 17, then the closest prime number is itself at a distance of 0. So 17 must be returned.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>The returned prime number must be greater than or equal to 'n'.</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

110 Solutions
50 Solvers

Last Solution submitted on Dec 01, 2020

Last 200 Solutions

Problem Comments

4 Comments

4 Comments

Show 1 older comment

Peng Liu on 23 Feb 2016

From test case 2, it seems that you are asking for the closest prime number no less than n. Please clarify this ambiguity in the problem. Otherwise, the answer to test case 2 is 19 (not 23), which is the closest prime number to 20.

Richard Zapor on 25 Feb 2016

Final statement in problem statement disagrees with Case #1 of n=3.

Ned Gulley on 25 Feb 2016

I made a few quick edits.

Jean-Marie Sainthillier on 29 Feb 2016

I suggest to update this problem with big primes.

Problem Recent Solvers50

Problem Tags

math primes

Community Treasure Hunt

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

Start Hunting!