determinant algorithm

[piopiwowarr]

Hi everyone,
I'm 3rd year informatics student on one of polish university and now i'm writing a thesis about numerical libraries. Now i have a problem, because i write about Armadillo library. I know, that library based on LAPACK. My question is how LAPACK calculated determinant of squere matrix? I must know algorithm which uses LAPACK. Is this LU decomposition? May this is Laplace(just joking)? I don't need full algorithm, i want how Lapact theoretically calculate determinant.
please respond quickly, it's 4:14am and i must deliver my thesis to 3pm...