PENTOMINOES is a C library which provides some utilities for manipulating pentominoes.
A pentomino is a shape formed by connecting 5 unit squares edgewise. Ignoring reflection and rotation, there are 12 distince pentominoes, nicknamed F, I, L, N, P, T, U, V, W, X, Y and Z.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
PENTOMINOES is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.
You can go up one level to the C source codes.