PROBLEM LINK:

Practice
Contest

Author:Iaroslav Tverdokhlib
Tester:Mahbub
Editorialist:Jingbo Shang

DIFFICULTY:

Hard

PREREQUISITES:

Circulant Matrix

PROBLEM:

Given a Circulant Matrix, determine whether it is full rank (i.e. non-zero determination, or the null space is trivial).

EXPLANATION:

There are a lot of properties about the determination and rank of Circulant Matrix can be found in Wikipedia:

http://en.wikipedia.org/wiki/Circulant_matrix

With these properties, we can try the Fast Fourier Transform as same as the setter. Also, there are some simpler solutions from the contestants. You can look into their codes for more details.

AUTHOR'S AND TESTER'S SOLUTIONS:

Solutions to be uploaded soon.

Author's solution can be found here.
Tester's solution can be found here.