Run spring-boot-school-timetabling from timefold 1.13.
When start solve, we obtain the optimal solution Score: 0hard/11soft.

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I am using some code generated by GTPChat.

I am working on a solution that needs too produce a timetable of students

I have been trying to create a solver configration file but it has given me this error:

I have an overconstrained problem with four planning variables on one planning entity, making them all nullable. If even one of these variables is null, the entity is regarded as not used in the solution. The construction heuristic (CH) phase runs too slowly with the default Cartesian product approach, so I am trying to optimize it. The variables are:

I have a timefold process that selects optimal departure times for railcars. The departure times are from 3 locations during each trip, (origin, serving yard, and facility).

I have model: