Problem 838. Check if number exists in vector

Created by Nichlas

Solve Later

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Solve

Solution Stats

11646 Solutions
5050 Solvers

Last Solution submitted on Apr 15, 2021

Last 200 Solutions

Problem Comments

5 Comments

5 Comments

Show 2 older comments

Richard Zapor on 17 Jul 2012

Add test vector a = -12;
b = [1,3,4,5,6,7,8,-12,2]; and rescore.
Better is add a=-randi(16); b= [1 2 3 a];
These will eliminate answers like #6.

frank mcnally on 15 Aug 2019

Tests allow incorrect solution to pass:

function y = existsInVector(a,b)
y=0
for i = 1:numel(b);
if i==a
y=1
break
end
end
end

Jyothsna Chintala on 21 Apr 2020

good

Nicholas Bitler on 26 Nov 2020

that was fun, took me a couple minutes

Qingyin Zhang on 29 Nov 2020

y = sum(b == a);

Solution Comments

Solution 4748072

1 Comment

1 Comment

Michael Green on 4 Feb 2021

One line :)

Solution 4143245

1 Comment

1 Comment

Cory Cunningham on 11 Dec 2020

I finally got it!

Solution 3602815

2 Comments

2 Comments

Swati on 10 Nov 2020

Can anyone tell me what's wrong in this code as I am getting the desired result in my laptop?

function y = existsInVector(a,b)
for i=1:length(b)
if a==b(i)
y=1
elseif
i=i+1
if i==3
y=0
end
end
end
end

arsenic 陈 on 11 Mar 2021

u have finished just theexample
function y = existsInVector(a,b)
y=1-isempty(find(a==b));
end

Solution 3277703

1 Comment

1 Comment

Joseph Martel-Foley on 19 Oct 2020

Add a test for multiple matches in the vector.

Solution 3205066

Solution 3064189

Solution 2905837

1 Comment

1 Comment

Peter Jan Struiving on 31 Mar 2021 at 13:45

Leading solutions are still broken

Solution 2586241

1 Comment

1 Comment

Piero Cimule on 19 Jun 2020

if true(find(b == a))
y = 1
else
y = 0
end

Solution 1936828

Solution 1173654

1 Comment

1 Comment

Ernest Woei on 27 Apr 2017

While evaluating the solution, the server encountered an error caused by temporary unavailability of MATLAB Service. Wait a few minutes for the MATLAB Service to return, and then rescore.

function y = existsInVector(a,b)
y=ismember(a,b);
end

Solution 899430

1 Comment

1 Comment

Joe Smith on 31 May 2016

There is a pre-made function for this.
y = ismember(a,b)

Solution 113925

1 Comment

1 Comment

Nichlas on 17 Jul 2012

Thanks! Have updated tests.

Problem Recent Solvers5050

Problem Tags

basic matlab vectors

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