Problem 84. Longest Divisor Run

Created by Cody Team

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1982 Solutions
982 Solvers

Last Solution submitted on Mar 28, 2023

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Solution 6624709

Solution 4627084

1 Comment

1 Comment

Rik on 19 Jan 2021

This scoring method leads to horrible coding. This is teaching horrible coding. No actual code should ever use ans.

Solution 3379238

2 Comments

2 Comments

bainhome on 25 Oct 2020

Second thought: I believe this algorithm is not bullet-proof. what if a = [4,6,12,18]?

liu wei on 5 Jul 2021

Yes, I found this problem, too

Solution 1278999

1 Comment

1 Comment

Santosh Kumar Choudhary on 30 Sep 2017

I am passing all test suit case in MATLAB 207b but I am getting this message:
While evaluating the solution, the server encountered an error caused by long running MATLAB code. Edit the code if needed and then submit.

Solution 1227237

1 Comment

1 Comment

yurenchu on 8 Jul 2017

Based on Gangyi's solution (Solution 57169). (And with thanks to Alfonso for directing my attention towards it. :-)

Solution 565894

1 Comment

1 Comment

yurenchu on 8 Jul 2017

Flawed solution; it fails when (for example) a = [2 10 20 30] .

Solution 66501

1 Comment

1 Comment

Mineralter on 12 Oct 2013

This Solution is a little difficult to obtain,but seems like an approach.

Solution 57169

1 Comment

1 Comment

bainhome on 26 Oct 2020

This iterationg is good indeed.

Solution 37656

1 Comment

1 Comment

Ramoflaple on 15 Jul 2015

good trick

Solution 17787

3 Comments

3 Comments

Peter Wittenberg on 26 Mar 2012

Yes, the size matters for this scoring, but using m(a)=0 makes for a grossly large vector. I'm not a big fan of this type of solution, which seems to make up the shortest solutions.

Alfonso Nieto-Castanon on 26 Mar 2012

If you do not care about Cody-'size' solution 66088 implements the same algorithm more efficiently (using sparse vectors instead of a 'grossly large' matrix)...

Alfonso Nieto-Castanon on 26 Mar 2012

my personal favourite nevertheless is Gangyi's 57169 solution, which seems to run typically twice as fast a my version...

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Problem 84. Longest Divisor Run

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Problem 84. Longest Divisor Run

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