discount(customer, product, 5.0 percent) :- premium(customer) , regular(product).
discount(customer, product, 7.5 percent) :- premium(customer) , luxury(product).
premium(customer) :- spending(customer, min 5000 euro, previous year).
luxury(Porsche).
regular(Honda).
spending(Peter Miller, min 5000 euro, previous year).
:-solve(discount(customer, product, amount)).
