class Employee {
    let name: String
    init(name: String) { self.name = name }
    func pay() -> Double { 0 }
}

class Manager: Employee {
    override func pay() -> Double { 6000 }
}

class Developer: Employee {
    override func pay() -> Double { 5000 }
}

let staff: [Employee] = [Manager(name: "Asha"), Developer(name: "Ben")]

for person in staff {
    print("\(person.name) earns \(person.pay())")
}
// Asha earns 6000.0
// Ben earns 5000.0