Problem 16. Return the largest number that is adjacent to a zero

Created by Cody Team

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14839 Solutions
4113 Solvers

Last Solution submitted on Dec 04, 2021

Last 200 Solutions

Problem Comments

4 Comments

4 Comments

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Gaik Tamazian on 17 Feb 2012

Two more tests:
1. Input x = [-4 -2 0 -4 -1 0]
Output y is -1.
2. Input x = [-9 -3 0 0 -5 0 -2 -1]
Output y is -2.

Geoff on 8 May 2012

Good comment, Gaik. A lot of solutions (including mine) will break with two consecutive zeros.

Nicolae Preda on 23 Sep 2013

Why: "Input x = [-9 -3 0 0 -5 0 -2 -1] Output y is -2."???
Output should be 0. It doesn't say anywhere that the number adjacent to a zero must be nonzero!

Kendale Greenidge-Bullock on 8 Dec 2017

This was challenging

Solution Comments

Solution 5010181

2 Comments

2 Comments

Ayesha Alfili HCT2021 on 7 Mar 2021

nice

Hello Say on 18 Sep 2021

good idea

1 Comment

1 Comment

Shuvo Kumar Paul on 28 Jul 2020

Very interesting problem

Solution 1248822

2 Comments

2 Comments

Eric Miller on 29 Sep 2017

I understand how this function works, but how did you know to use [1 0 1] for the convolution?

Hello Say on 18 Sep 2021

cool

Solution 1224006

1 Comment

1 Comment

Salvatore Lacava on 3 Jul 2017

Quiet hard, but satisfying! :)

Solution 1123836

2 Comments

2 Comments

shahriar memaran on 24 Feb 2017

It is really cool to see someone has the exact chain of thoughts as you .... !!!

Jordan Covert on 17 Jan 2020

I believe size(x,2) is equivalent to length(x). Great solution though! Made me realize where I put in too much work.

Solution 869724

1 Comment

1 Comment

Atsushi Ueno on 10 Apr 2016

Because of 2 bytes space charactor

Solution 793614

1 Comment

1 Comment

Fatpuss on 13 Dec 2015

Damn that's a lot higher score than I was expecting.

Solution 729104

1 Comment

1 Comment

Jean-Yves Tinevez on 4 Sep 2015

Trying to emulate imdilate.

Solution 716831

1 Comment

1 Comment

Nicholas Hortance on 18 Aug 2015

Hi everyone. I realized this code is very large and cannot be run on this website because of the many loops that it has to go through. It works on matlab so if anyone could help me keep the general form of it but have it cut down in the number of loops that would be great. Thanks.

Solution 667827

1 Comment

1 Comment

Meade on 7 May 2015

the imdilate function apparently can't be used... this is a clumsy clumsy workaround

Solution 551834

1 Comment

1 Comment

Mattias on 3 Jan 2015

This one was hard. Tried my best but couldn't get it shorter

Solution 508476

2 Comments

2 Comments

Brad on 5 Oct 2014

I think the test suite needs a test for a = [0 0 0 0]. I passed with the above code but would not pass this case.

Meade on 8 May 2015

I ended up with the same logic, I'm glad I wasn't the only one.

It's a shame this is basically a verbose reworking of the imdilate function (which is not accessible for this challenge)

Solution 439808

1 Comment

1 Comment

hubert andre on 13 Apr 2016

well, this looks a bit.. long?

Solution 372342

1 Comment

1 Comment

Ryan on 22 Dec 2013

I suppose overt is more at it. This will catch multiple consecutive zeros. I suppose I could have put comments too. Not to mention it's clocking 10^-6sec. Why do these Cody problems go by size isn't speed incredibly more important in computational programming.

Solution 254391

1 Comment

1 Comment

Florent Hennart on 5 Jun 2013

regexp should really be banned from problems not related with word handling...

Solution 230859

1 Comment

1 Comment

Saptarshi Roy on 10 Sep 2013

smart solution.

Solution 190537

2 Comments

2 Comments

Peter on 10 Mar 2013

This solution gives the wrong value if the largest value is at the end of the vector. For example for x = [1 0 2 0 3] it returns 2 instead of 3.

Ned Gulley on 12 Mar 2013

Thanks for the tip!

Solution 141637

1 Comment

1 Comment

Lone Christoffersen on 24 Sep 2012

It can handle adjacent zeroes.

Solution 113869

1 Comment

1 Comment

Peter Koetzing on 17 Jul 2012

No way that the leading solution is the least complex one! The rating function is questionable.

Solution 95807

1 Comment

1 Comment

Amy on 17 Jul 2012

Fails when the max value output should be negative and the last value of the input vector is zero, e.g. a = [5 4 -1 0 -2 0 -5 0]. Should return -1, but returns 0.

Solution 41700

1 Comment

1 Comment

prithvi on 15 Feb 2012

this should work

Solution 24840

1 Comment

1 Comment

Ze Zhang on 17 Mar 2015

Nice! It's quite clever to put the front and rear in pairs.

Solution 20360

1 Comment

1 Comment

Siva on 18 Apr 2012

Peter's comment about Solution 20356 appears to apply here as well.

Solution 20356

2 Comments

2 Comments

Peter on 8 Mar 2012

This solution gives the wrong value if the largest value is at the end of the vector, for example for x = [1 0 2].

tqy on 20 Apr 2012

It's wrong with the input [0 9 0].

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Problem 16. Return the largest number that is adjacent to a zero

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Problem 16. Return the largest number that is adjacent to a zero

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