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Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today. # Generics Code Challenge Task 5 of 5

I'm stuck on the very last task of the code challenge. Any help would be appreciated!

Add a second function named dequeue, that takes no parameters, and returns an optional Element. Since a queue follows a first in, first out policy, dequeue returns the element that was added first. If the queue is empty, return nil For example, given the queue: [1,4,9,7], calling dequeue returns 1, and the resulting queue is [4,9,7]. Note: Dequeue removes the first element from the array

generics.swift
```struct Queue<Element> {
var array = [Element]()
var isEmpty: Bool {
if array.isEmpty {
return true
} else {
return false
}
}

var count: Int {
return array.count
}

mutating func enqueue(_ item: Element) {
self.array.append(item)
}

mutating func dequeue() -> Element? {
if self.array.isEmpty == false {
self.array.remove(at: 0)
return self.array
} else {
return nil
}

}
}
``` Ah I found the solution. Super simple since I read that the remove(at: Int) actually returns the removed item. So, I simply adjusted the code to reflect it.

```struct Queue<Element> {
var array = [Element]()
var isEmpty: Bool {
if array.isEmpty {
return true
} else {
return false
}
}

var count: Int {
return array.count
}

mutating func enqueue(_ item: Element) {
self.array.append(item)
}

mutating func dequeue() -> Element? {
if self.array.isEmpty == false {
return self.array.remove(at: 0)
} else {
return nil
}

}
}
```

Bryce Vernon's answer is correct I'm adding an alternative solution below with a (very) slightly different implementation of the `dequeue()` instance method just for reference / for anyone curious (a.k.a., for when I have to come back to this six months from now):

```struct Queue<Element> {
var array: [Element] = []

var isEmpty: Bool {
if array.isEmpty {
return true
} else {
return false
}
}

var count: Int {
return array.count
}

mutating func enqueue(_ newItem: Element) {
array.append(newItem)
}

mutating func dequeue() -> Element? {
if array.isEmpty == false {
return array.removeFirst()
} else {
return nil
}
}
}
``` PLUS

I like your's Bryce, here's a cleaner version yet.

```mutating func dequeue() -> Element? {
if array.isEmpty {
return nil
}
return array.removeFirst()
}
```