Abstract: The present disclosure provides a multilevel combinatorial optimizer for resource planning that identifies resource use preferences for a set of resources and a set of tasks to be performed; assigns resources to tasks to generate a strict-priority assignment set; in response to reaching a process break: identifies a subset of resources below a specified priority level; assigns the subset to unassigned tasks until each task is fully assigned to provide a full-assignment assignment set; in response to completing assignments for the set of tasks: rectifying inversions in the full-assignment assignment set by: selecting a tuple size for swapping the resources among tasks; identifying tuples of assignments that include an inversion; swapping the assignments identified in the tuples to remove the inversion and update the full-assignment assignment set to a reduced-inversion assignment set; and in response to the reduced-inversion assignment set including no inversions, outputting the reduced-inversion assignment se