PSHTBRTH - Editorial

Can someone explain how the sparse grundy number is calculated for the matrix above in detail.
I don’t understand the way to find the grundy value for all the possible position from the first position ans so on.

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can any one explain what is happening in 6 loops to calculate grundy values

those 6 loops check all the possible state that can be visited from the current state.
It checks whether a submatrix has all ones in it or not. if it is having all ones then we clear that submatrix and goes to a lower state otherwise we break the loop.
Hope it helps :slight_smile:

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Hi Everyone!

I was finally able to make a video editorial on this problem. Here is the link:
Pishty and Birthday

Pishty Image

If you need some theory on Grundy Numbers or Sprague Grundy, you can check out the respective videos.

If you have any doubts, please don’t hesitate to get them clarified. Looking forward to your suggestions.



Thanks dude!! I REALLY was carving for a video editorial for this one!! Made my day!! THANKS AGAIN!! :slight_smile:


Thanks @vijju123 :slight_smile:

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