Abstract: A device and a method for solving an answer set programming program. The method includes receiving constant symbols and a set of rules for the constant symbols that comprises the constant symbols, wherein the answer set programming program is defined depending on the set of rules, determining a solution to the answer set programming program that comprises at least one of the constant symbols, determining a constraint depending on a cost for the solution, selecting in the solution at least one constant symbol, redetermining the solution as a result of an answer set programming program that is defined depending on the set of rules, and the constraint, wherein when solving the answer set programming program for redetermining the solution, the at least one constant symbol is treated as variable in the set of rules.

Abstract: Machine scheduling for executing a set of jobs of a task with a set of machines. The scheduling includes determining in a first iteration a first schedule that solves an optimization problem, the optimization problem is defined by a set of rules that assign the set of jobs to the set of machines, the first schedule maps each job to one machine of the set that is capable of processing this job, an execution of jobs assigned to a machine are scheduled to be finished in a machine span, and in a second iteration either determining a constraint for a machine span and determining a second schedule that solves the optimization problem for the set of jobs and the set of machines under the constraint, or determining a second schedule that solves the optimization problem for a sub-set of the set of jobs and of the set of machines.