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isaac brakha
6,781 PointsWhy is my code wrong Challenge Build iphone app
class Point { var x: Int var y: Int
init(x: Int, y: Int) { self.x = x self.y = y } }
class Machine { var location: Point
init() { self.location = Point(x: 0, y: 0) }
func move(_ direction: String) { print("Do nothing! I am a machine!") } }
// Enter your code below
class Robot: Machine {
override init() {
self.location = location
func move(_ direction: String) {
let direction: String
switch true {
case direction == "Up": self.location.y += 1
case direction == "Down": self.location.y -= 1
case direction == "Left": self.location.x -= 1
case direction == "Right": self.location.x += 1
default: print("Bye")
}
}
}
}
class Point {
var x: Int
var y: Int
init(x: Int, y: Int) {
self.x = x
self.y = y
}
}
class Machine {
var location: Point
init() {
self.location = Point(x: 0, y: 0)
}
func move(_ direction: String) {
print("Do nothing! I am a machine!")
}
}
// Enter your code below
class Robot: Machine {
override init() {
self.location = location
func move(_ direction: String) {
let direction: String
switch true {
case direction == "Up": self.location.y += 1
case direction == "Down": self.location.y -= 1
case direction == "Left": self.location.x -= 1
case direction == "Right": self.location.x += 1
default: print("Bye")
}
}
}
}
1 Answer
Rickey Paape
24,122 PointsThere are a few reasons.
- Since you are overriding the init method, you will need to call super.init() before you can do anything else.
- You initialize the constant direction when you call the move function, so you cannot initialize it again with the let direction: String line.
- You will need to pass the direction constant into the switch statement rather than true.
- Once you correct #3, each case in the switch statement already does the equivalent comparison so there is no need to have "direction ==" in any of the cases listed.
The correct code should be:
override init() {
super.init()
self.location = location
func move(_ direction: String) {
switch direction {
case "Up": self.location.y += 1
case "Down": self.location.y -= 1
case "Left": self.location.x -= 1
case "Right": self.location.x += 1
default: print("Bye")
}
}
}