The first step is to construct the \( M \)-scheme basis of Slater determinants. Here \( M \)-scheme means the total \( J_z \) of the many-body states is fixed.

The steps could be:

• Read in a user-supplied file of single-particle states (examples can be given) or just code these internally;
• Ask for the total \( M \) of the system and the number of particles \( N \);
• Construct all the \( N \)-particle states with given \( M \). You will validate the code by comparing both the number of states and specific states.