 }
 
 class Apartment3 {
-    let number: Int
-    init(number: Int) { self.number = number }
+    let unit: String
+    init(unit: String) { self.unit = unit }
     weak var tenant: Person3?
-    deinit { print("Apartment #\(number) is being deinitialized") }
+    deinit { print("Apartment #\(unit) is being deinitialized") }
 }
 
 var james: Person3?
 var number74: Apartment3?
 
 james = Person3(name: "James Appleseed")
-number74 = Apartment3(number: 74)
+number74 = Apartment3(unit: "74")
 
 james!.apartment = number74
 number74!.tenant = james

        print("\(name) is being deinitialized")
    }
}

var paragraph: HTMLElement? = HTMLElement(name: "p", text: "hello, world")
print(paragraph!.asHTML())

}

class CreditCard {
    let number: UInt64
    unowned let customer: Customer
    init(number: UInt64, customer: Customer) {
        self.number = number
        self.customer = customer
    }
