Problem 32. Most nonzero elements in row

Created by Cody Team

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Given the matrix a, return the index r of the row with the most nonzero elements. Assume there will always be exactly one row that matches this criterion.

Example:

 Input  a = [ 1 2 0 0 0
              0 0 5 0 0 
              2 7 0 0 0
              0 6 9 3 3 ]
 Output r is 4

Solve

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Last Solution submitted on Mar 25, 2025

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11 Comments

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Rodolfo on 12 Mar 2013

How am I wrong here?
"a = [ ...
1 0 0;
0 0 0;
0 0 0;
0 0 0;
0 2 3];
r_correct = 5;"
My code says 2, I think it's correct, what am I missing?

Tim on 12 Mar 2013

It wants the number of the row with the most nonzeros.

Rodolfo on 12 Mar 2013

Thank you Tim! I feel like a fool, but that'll teach me to read the requirements more carefully. Hopefully.

Gabor Levai on 8 Sep 2016

Great Problem!

MEI HUEI LIM on 5 Jan 2017

nice

DilRavsh on 20 Aug 2017

Love this one

Basil C. on 19 Feb 2018

Piece of cake

Gani on 8 Feb 2019

nice

Alexander on 12 Feb 2019

easy :) but nice

Rahul Gulia on 20 Jul 2020

Could you please check my solution.
How come the solution example 2, 3 and 4 have r= 3, 5 and 4. When it should have been r = 4, 3 and 1.
As these are the maximum number of zeros in any of the given row.

Can someone please give me a hint on how the solutions are provided so different?

Rubeena Aafreen on 22 Oct 2020

What are these matrices in last 3 test cases? Can someone help

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Problem 32. Most nonzero elements in row

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Problem 32. Most nonzero elements in row

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