primary.hpp

primary.hpp is the foundation of math.hpp.

basic.hpp

mod.hpp

fft.hpp

fast Fourier transform

It contains dft and idft in namespace FFT.

The size of $a$ is a pow of $2$ before you use dft(a) or idft(a)

ntt.hpp

number theory transform

It contains dft and idft in template classs NTT.

The template $M$ should be NTT-friendly, and size of $a$ is a pow of $2$ less that $10^6$ before you use dft(a) or idft(a)

fmt.hpp

fast Mobius transform