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iOS Object-Oriented Swift Value vs Reference Types Final Challenge

I need help on the second task...

What to do on the second task? There is no properties to call.

Vehicle.swift
class Vehicle {
    let wheels: Int
    let doors: Int

    // Designated initializer
    init(wheels:Int, doors:Int){

    }
}

class Car: Vehicle {
    // A car must default to 4 wheels and 4 doors
    init(){
      // call super.init
    }
}

1 Answer

Richard Lu
Richard Lu
20,185 Points

Hey Roman,

The follow challenge is to test you on inheritance. Since the class Car inherits from Vehicle, Car automatically has the ability to call from it's superclass.

init(wheels:Int, doors:Int)

You'll need to use the super classes initializer:

class Vehicle {
    let wheels: Int
    let doors: Int

    // Designated initializer
    init(wheels:Int, doors:Int){
        self.wheels = wheels
        self.doors = doors
    }
}

class Car: Vehicle {
    init(){
       super.init(wheels: 4, doors: 4) // A car must default to 4 wheels and 4 doors
    }
}

Enjoy!~