Problem 1172. Wheat on a chessboard pt 1

Created by Robert Turner

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Last Solution submitted on Apr 10, 2021

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Ken Campbell on 5 Jan 2013

Shouldn't the solution for n=-1 be NaN, rather than 'NaN' which is a character array?

Aurelien Queffurust on 7 Jan 2013

I agree with Ken , we expect NaN and not the string 'NaN'

James on 7 Jan 2013

I believe you should also change the assert for the case n=-1 to be isequalwithnan, since isequal(NaN,NaN) is false.

Aurelien Queffurust on 8 Jan 2013

yeap you have just rescored the problem but you need to use isequalwithnan,

Prateep Mukherjee on 8 Jan 2013

actually you need to use isequalwithequalnans

Jan Orwat on 11 Apr 2014

tests 5 and 6 does not work properly. those numbers are out of precision, and for test 6 it couldn't be fixed even with uint64 used instead of type double

Massimo Zanetti on 19 Oct 2016

This problem is simply wrong. The right answer is

sum(1:2^(n^2-1))

if we where to sum ALL the grains on the board....

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Solution 498402

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Grzegorz Knor on 10 Sep 2014

Sorry for cheating, I didn't notice that there is string 'NaN' in test suite.

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Problem 1172. Wheat on a chessboard pt 1

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Problem 1172. Wheat on a chessboard pt 1

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