generating 2D bit array variants with specific algorythm
Dave Angel
davea at davea.name
Fri Nov 7 14:34:11 EST 2014
Robert Voigtländer <r.voigtlaender at gmail.com> Wrote in message:
> Hi,
>
> I need to generate all variants of a 2D array with variable dimension sizes which fit a specific rule. (up to 200*1000)
>
> The rules are:
> - Values are only 0 or 1
> - the sum of each line bust be 1
> - only valid results must be generated (generating all and only returning the valid results takes to long; that's what I tried already)
>
> So for a 2x2 array these would be the valid results:
>
> 10
> 01
>
> 01
> 10
>
> 10
> 10
>
> 01
> 01
>
>
> Must be possible with nested loops and a counter per line. But I don't get it.
If the matrix is m by n, then there are 2**n possibilities for
each row. But only n of them are legal by your rules. So your
problem is just a matter of counting in base n, all the possible
m digit numbers.
--
DaveA
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