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# Robots.swift not works?

// Enter your code below class Robot: Machine { override func move(direction: String) { switch direction { case "Up": self.location.y += 1 print("hola") case "Down": self.location.y -= 1 case "Left": self.location.x -= 1 case "Right": self.location.x += 1 default: break } } } let rob = Robot() rob.move(direction: "Up") print(rob.location.x)

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! Im a machine!")
}
}

class Robot: Machine {
override func move(direction: String) {
switch direction {
case "Up":
self.location.y += 1
print("hola")
case "Down":
self.location.y -= 1
case "Left":
self.location.x -= 1
case "Right":
self.location.x += 1
default: break
}
}
}
let rob = Robot()
rob.move(direction: "Up")
print(rob.location.x)
```

Hi David,

If you add the underscore in the overridden `move` method, your code will pass the challenge:

```// Enter your code below
class Robot: Machine {
override 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: break
}
}
}
```

Steve.