     override init(name: String) {
         super.init(name: name)
     }
-    
+
     override func sound() -> String {
         return "baaaa"
     }

class Animal {
    let name: String
    
    init(name: String) {
        self.name = name
    }
    
    func sound() -> String {
        preconditionFailure("This method must be overridden")
    }
    
    func speak() -> String {
        return "\(self.name) says \(self.sound())"
    }

    override init(name: String) {
        super.init(name: name)
    }

    override func sound() -> String {
        return "neigh"
    }
