1. A method comprising: determining a plurality of values, wherein assignment of a set from the plurality of values to one or more constrained variables of a candidate solution causes the candidate solution to comply with a constraint condition of an optimization problem, wherein the candidate solution complies with the constraint condition prior to being mutated via a computer-based simulation that tests fitness of the candidate solution; after the candidate solution is mutated, determining that the candidate solution fails to comply with the constraint condition; and assigning the set from the plurality of values, which is randomly selected from the plurality of values, to the one or more constrained variables of the candidate solution.