cat.swift

class Cat : Eye{
    var isIdle: Bool? = true
    
    func closeEyesAndSleep() {
        if isIdle == true{
            print("Cat is sleeping now")
        }else{
            print("Cat will NOT sleep now")
        }
    }
    
    func openEyesAndLookAround() {
        print("Cat is looking around")
    }
}

extension Cat : Animal{
    func run() {
        isIdle = true
        print("Cat is running now")
    }
    
    func stop() {
        isIdle = false
        print("Cat has stopped now")
    }
}