war.swift

protocol WarCapable {
    var topSpeed : Double {get set}
    var shotsPerMinute : Int {get set}
}

protocol SpyCapable {
    var numberOfCameras : Int {get set}
}

class WarTank : WarCapable {
    var topSpeed: Double = 100.0
    var shotsPerMinute: Int = 5
}

class SpyJeep : WarCapable, SpyCapable{
    var topSpeed: Double = 200
    var shotsPerMinute: Int = 1
    var numberOfCameras: Int = 5
}

class SpyBike : SpyCapable{
    var numberOfCameras: Int = 1
}

//War tank objects
var t10 = WarTank()

var t11 = WarTank()
t11.topSpeed = 110.0


//Spy Jeep Objects
var sj10 = SpyJeep()

var sj11 = SpyJeep()
sj11.topSpeed = 190.0

// Spy Bike Objects
var sp10 = SpyBike()

var sp11 = SpyBike()
sp11.numberOfCameras = 2

// Extensions
extension WarCapable{
    func canTravelFaster(item : WarCapable)->Bool{
        return self.topSpeed > item.topSpeed
    }
}

t10.canTravelFaster(item: t11)
// returns false

sj11.canTravelFaster(item: t11)
// returns true