Problem 803. Twist 'n' Match

Created by Ned Gulley

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220 Solutions
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Last Solution submitted on Jul 31, 2022

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6 Comments

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Jean-Marie Sainthillier on 21 Feb 2017

A lot of solutions don't work with something like n=5 and m=0

Jean-Marie Sainthillier on 22 Feb 2017

Not at all...
For n-by-n matrix, m=1 if n is odd number.

Asif Newaz on 1 Feb 2020

ur problems are really interesting

Ned Gulley on 3 Feb 2020

Thanks Asif!

Rafael S.T. Vieira on 1 Aug 2020

This problem has some issues because some pairs (n,m) do not have a solution. For instance, it is impossible to find a matrix such that m = n^2 -1 since a rotation pivot does not move. Moreover, there are floor((n^2)/4) cycles of numbers, and when we match the cycle beginning with its end, it creates two matches. It is possible to do some manipulations to have an m greater than n^2 - floor((n^2)/4), but not always.

A C on 26 Oct 2020

can you give an example of a matrix before and after?

Solution Comments

Solution 2765800

1 Comment

1 Comment

Rafael S.T. Vieira on 1 Aug 2020

My code fails for some of the cases I've mentioned. The current leading solution does better (finding some solutions my code can't), yet sometimes it enters into an infinite loop.

Solution 2114985

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1 Comment

Asif Newaz on 2 Feb 2020

i had no idea this was gonna work :p

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Problem 803. Twist 'n' Match

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Problem 803. Twist 'n' Match

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