onlydmc123's blog

Fast Fourier Transform, Multiplying Polynomials , Need Help
By onlydmc123, 10 years ago, In English

I was searching a lot to understand FFT, I know FFT has many applications, but I need it for multiplying polynomials. I Found this: http://www.cs.cmu.edu/afs/cs/academic/class/15451-s10/www/lectures/lect0423.txt. and it was really helpful to understand its nature, there is given algorithm in pseudo-C too, but I don't know how to implement it in C or C++. Can you suggest to me clean impelementation of FFT, where the inputs are two polynomials and output is multiplication of them?

Thanks in advance.

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10 years ago, # |
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mamba chi ha mamba chi ???

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10 years ago, # |
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From my library: http://ideone.com/tbHUN7

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    10 years ago, # ^ |
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    Note that complex<> is slow. It's better to use hand-written struct.

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10 years ago, # |
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I recently learned FFT myself. For theory I read CLRS. It has a whole chapter on the topic. For implementation I used http://e-maxx.ru/algo/fft_multiply. I used the implementation to get AC in UVa 12879 — Golf Bot.

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8 years ago, # |
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This is my C++ program https://ideone.com/jR993P, that is quite complete except enter 2 input polynomials ( this for you ). I hope that can help you

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