J. Férard 2023-03-04.
Let three functions:
- a function p: task × time_slot ↦ priority (0 means: not task for this time-slot)
- a function aff1: employee × time_slot ↦ affinity (0 means: not available for this time-slot)
- a function aff2: employee × task ↦ affinity (0 means: not concerned by this task)