Graphical decrypt is an exercise on the algebraic cryptology based on
pseudo-random sequences generated by primitive polynomials over a finite field
_{q}.
You will be presented a picture composed of *n*×*n* pixels, crypted
by such a sequence. This picture has q colors, each color representing an
element of _{q}.

And your goal is to decrypt this crypted picture, by finding back the primitive polynomial as well as the starting terms which determine the pseudo-random sequence.