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Why 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!") } }

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")

}

}

}
```

}

robots.swift
```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!")
}
}

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")

}

}

}

}
```

There are a few reasons.

1. Since you are overriding the init method, you will need to call super.init() before you can do anything else.
2. You initialize the constant direction when you call the move function, so you cannot initialize it again with the let direction: String line.
3. You will need to pass the direction constant into the switch statement rather than true.
4. 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")

}
}
}
```