Abstract: An AI (Artificial Intelligence) system comprising: the input means 81 accepts input of multiple candidate solutions to an optimization problem in which an objective function is express as an inner product of a feature and weight, or expressed in a bilinear form, and weight of the objective function; the optimal solution determination means 82 determines as an optimal solution, among the candidate solutions, the candidate solution that maximizes the inner product with the weight of the objective function or the candidate solution that maximizes a value of the bilinear form; and the output means 83 outputs the optimal solution.