[Click Here for Problem](http://www.usaco.org/index.php?page=viewproblem2&cpid=366)↵
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[Chinese Solution](http://cbdcoding.blogspot.in/2015/04/usaco-2013-gold-bessie-shuffle.html), since USACO does not have an official solution for the problem above.↵
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I had a lot of trouble with the implementation of this question, so I looked up this solution online. Google Translate could only do so much for the page (the only solution I could find), but I think I was able to discern the following from the code:↵
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1) The array "per" reverses the permutation process, and length of 31 represents a bitmask of that length.,↵
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2) The idea behind the "per" is that the result of a number of consecutive permutations can be assembled in logarithmic time., and↵
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3) The variable "num" in the third main loop functions as a mask.↵
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However, I do not fully understand the purpose of "bot", "now", and "k" in the third main loop, and the mathematics in the first and third main loops.↵
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I would appreciate an explanation for these parts of the solution.↵
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Thanks in advance!
↵
[Chinese Solution](http://cbdcoding.blogspot.in/2015/04/usaco-2013-gold-bessie-shuffle.html), since USACO does not have an official solution for the problem above.↵
↵
I had a lot of trouble with the implementation of this question, so I looked up this solution online. Google Translate could only do so much for the page (the only solution I could find), but I think I was able to discern the following from the code:↵
↵
1) The array "per" reverses the permutation process, and length of 31 represents a bitmask of that length
↵
2) The idea behind the "per" is that the result of a number of consecutive permutations can be assembled in logarithmic time
↵
3) The variable "num" in the third main loop functions as a mask.↵
↵
However, I do not fully understand the purpose of "bot", "now", and "k" in the third main loop, and the mathematics in the first and third main loops.↵
↵
I would appreciate an explanation for these parts of the solution.↵
↵
Thanks in advance!
