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# In the editor you've been provided with two classes - Point to represent a coordinate point and Machine. The machine has

how solve it

classes.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'm a machine!")
}
}
class Robot: Machine {
var location2: Point
var x1: Int
var y1: Int
override init() {
super.init(direction: String,x: x1,y: y1)
x1 = x
y1 = y
}
override func move(direction: String, x: x1, y: y1) {
switch direction {
case "Up":
++y1
case "Down":
--y1
case "Left":
--x1
case "Right":
--x1
default:
break
}
}
}
// Enter your code below
```

Junaid, good start, but as you saw there are some problems. First, you did too much work. You don't need the member variables in Robot, or the initializer. What variables are needed are inherited from Machine. And the default member-wise initializer works fine.

Second, in the overridden function you only need one parameter: direction.

Third, in the switch statement you need to reference the x and y variables of the Point object location, and increment them correctly. Increment should be in the form x++ or x--, not ++x or --x. With these changes you get:

```class Robot: Machine {

override func move(direction: String) {
switch direction {
case "Up":
location.y++
case "Down":
location.y--
case "Left":
location.x--
case "Right":
location.x++
default:
break
}
}
}
```

Hope this helps.