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# Can't get these errors to GO AWAY!

enum Direction { case up, down, left, right }

protocol Movable { func move(_ direction: Direction, by distance: Int) }

protocol Destructable { func descreaseLife(by factor: Int) }

protocol Player: Destructable { var position: Point { get set } var life: Int { get set } init(x: Int, y: Int) }

protocol Attacker { var strength: Int { get } var range: Int { get }

```func attack(player: Player)
```

}

struct Point { let x: Int let y: Int

```init(x: Int, y: Int) {
self.x = x
self.y = y
}

/// Returns the surrounding points in range of
/// the current one
func points(inRange range: Int = 1) -> [Point] {
var results = [Point]()

let lowerBoundOfXRange = x - range
let upperBoundOfXRange = x + range

let lowerBoundOfYRange = y - range
let upperBoundOfYRange = y + range

for xCoordinate in lowerBoundOfXRange...upperBoundOfXRange {
for yCoordinate in lowerBoundOfYRange...upperBoundOfYRange {
let coordinatePoint = Point(x: xCoordinate, y: yCoordinate)
results.append(coordinatePoint)
}
}

return results
}
```

}

// Enemy

class Enemy: Player, Attacker, Movable { var life: Int = 2 var position: Point var strength: Int = 5 var range: Int = 2

```required init(x: Int, y: Int) {
self.position = Point(x: x, y: y)
}

func decreaseLife(by factor: Int) {
life -= factor
}

func attack(player: Player) {
player.descreaseLife(by: strength)
}

func move(_ direction: Direction, by distance: Int) {
switch direction {
case .up: position = Point(x: position.x, y: position.y + 1)
case .down: position = Point(x: position.x, y: position.y - 1)
case .right: position = Point(x: position.x + 1, y: position.y)
case .left: position = Point(x: position.x - 1, y: position.y)
}
```

}

// Tower class Tower { let position: Point var range: Int = 1 var strength: Int = 1

```init(x: Int, y: Int) {
self.position = Point(x: x, y: y)
}

func fire(at enemy: Enemy) {
if isInRange(of: enemy) {
enemy.decreaseLife(by: strength)
print("Gotcha")
} else {
print("Darn! Out of range!")
}
}

func isInRange(of enemy: Enemy) -> Bool {
let availablePositions = position.points(inRange: range)

for point in availablePositions {
if point.x == enemy.position.x && point.y == enemy.position.y {
return true
}
}

return false
}
```

}

Hi martel,

I saw 2 errors in your code:

• The first saying that the class enemy didn't conform to the protocol Destructable. It is just because of a typing error. You wrote "descreaseLife" instead of "decreaseLife".

• The second: a "}" is missing in the end of the tower class.

here is the code:

```enum Direction {
case up, down, left, right
}

protocol Movable {
func move(_ direction: Direction, by distance: Int) }

protocol Destructable {
func decreaseLife(by factor: Int) }

protocol Player: Destructable {
var position: Point { get set }
var life: Int { get set }
init(x: Int, y: Int) }

protocol Attacker {
var strength: Int { get }
var range: Int { get }

func attack(player: Player)
}

struct Point {
let x: Int
let y: Int

init(x: Int, y: Int) {
self.x = x
self.y = y
}

/// Returns the surrounding points in range of
/// the current one
func points(inRange range: Int = 1) -> [Point] {
var results = [Point]()

let lowerBoundOfXRange = x - range
let upperBoundOfXRange = x + range

let lowerBoundOfYRange = y - range
let upperBoundOfYRange = y + range

for xCoordinate in lowerBoundOfXRange...upperBoundOfXRange {
for yCoordinate in lowerBoundOfYRange...upperBoundOfYRange {
let coordinatePoint = Point(x: xCoordinate, y: yCoordinate)
results.append(coordinatePoint)
}
}

return results
}
}

// Enemy

class Enemy: Player, Attacker, Movable {
var life: Int = 2
var position: Point
var strength: Int = 5
var range: Int = 2

required init(x: Int, y: Int) {
self.position = Point(x: x, y: y)
}

func decreaseLife(by factor: Int) {
life -= factor
}

func attack(player: Player) {
player.decreaseLife(by: strength)
}

func move(_ direction: Direction, by distance: Int) {
switch direction {
case .up: position = Point(x: position.x, y: position.y + 1)
case .down: position = Point(x: position.x, y: position.y - 1)
case .right: position = Point(x: position.x + 1, y: position.y)
case .left: position = Point(x: position.x - 1, y: position.y)
}
}
}

// Tower
class Tower {
let position: Point
var range: Int = 1
var strength: Int = 1

init(x: Int, y: Int) {
self.position = Point(x: x, y: y)
}

func fire(at enemy: Enemy) {
if isInRange(of: enemy) {
enemy.decreaseLife(by: strength)
print("Gotcha")
} else {
print("Darn! Out of range!")
}
}

func isInRange(of enemy: Enemy) -> Bool {
let availablePositions = position.points(inRange: range)

for point in availablePositions {
if point.x == enemy.position.x && point.y == enemy.position.y {
return true
}
}

return false
}
}
```

Anthony