Problem 43738. Negative without '-'

Created by JD

Solve Later

Simple: return a negative number without using the '-' sign.

Thanks to Problem 813 for help with test suite.

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130 Solutions
19 Solvers

Last Solution submitted on Nov 29, 2019

Last 200 Solutions

Problem Comments

1 Comment

1 Comment

James on 5 Feb 2019

JD, I think I figured out why Binbin and I (and more than likely a good number of other players) are having issues with your test suite. I think your "assert(isempty(strfind(filetext, '0')),'0 forbidden')" line is catching everyone who has the digit 0 in their MATLAB ID number. Binbin and I have that, while you do not. I just hacked the test suite, and tried a non-hacking correct answer from Alfonso...with the same result - my solution failed because 0 is forbidden.

Solution Comments

Solution 1109801

2 Comments

2 Comments

James on 24 Jan 2017

I'm also curious about the test suite, Binbin. I'm not quite sure why
y = diff([x+1 1]); fails the test suite.

JD on 7 Jul 2017

Binbin, James - I am not sure why either of your solutions didn't work. I submitted them, and they both passed... Maybe try resubmitting...? Maybe there's a bug in Cody...?

Solution 1077095

3 Comments

3 Comments

Binbin Qi on 12 Jan 2017

why this solution is wrong?

James on 24 Jan 2017

Sorry for the double comment, but I can't delete the one I posted under my solution.

I'm also curious about the test suite, Binbin. I'm not quite sure why my solution of "y = diff([x+1 1]);" fails the first test suite. I don't see any of the forbidden words in there.

JD on 7 Jul 2017

Binbin, James - I am not sure why either of your solutions didn't work. I submitted them, and they both passed... Maybe try resubmitting...? Maybe there's a bug in Cody...?

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Problem 43738. Negative without '-'

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Problem 43738. Negative without '-'

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