Linear recursion problem — help me find it

Revision en1, by W4yneb0t, 2017-05-24 18:56:00

I remember reading this problem in some contest, but I don't remember where. I think the contest was 2016 or so. I searched on a few websites with no luck. Do you happen to know what contest it was?

The problem is: Given integers a1, ..., an, We define x0 = 1 and for every . Find xn. The solution was O(n * polylog(n)) with FFT.


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en1 English W4yneb0t 2017-05-24 18:56:00 419 Initial revision (published)