FactoryMethod.swift

protocol RentalCar {
    var name:String { get }
    var passengers:Int { get }
    var pricePerDay:Float { get }
}

class Compact : RentalCar {
    var name = "VW Golf"
    var passengers = 3
    var pricePerDay:Float = 20
}

class Sports : RentalCar {
    var name = "Porsche Boxter"
    var passengers = 1
    var pricePerDay:Float = 100
}

class SUV : RentalCar {
    var name = "Cadillac"
    var passengers = 8
    var pricePerDay:Float = 75
}

class Minivan : RentalCar {
    var name = "Chevrolet"
    var passengers = 14
    var pricePerDay:Float = 40
}

class CarSelector {
    class func selectCar(passengers:Int) -> String? {
        var car:RentalCar?
        switch (passengers) {
        case 0...1:
            car = Sports()
        case 2...3:
            car = Compact()
        case 4...8:
            car = SUV()
        case 9...14:
            car = Minivan()
        default:
            car = nil
        }
        return car?.name
    }
}

let passengers = [1 ,3, 5]
for p in passengers {
    print("\(p) passengers: \(CarSelector.selectCar(p))")
}