Sha256: c3cd2aa46fb0770580f9594a9f00180b8184c8fd3a4645b20a6b0c887922fc57
Contents?: true
Size: 1.75 KB
Versions: 71
Compression:
Stored size: 1.75 KB
Contents
class Node<T> {
var value: T? = nil
var next: Node? = nil
var prev: Node? = nil
init() {
}
init(value: T) {
self.value = value
}
}
class Deque<T> {
var count: Int = 0
var head: Node<T>
var tail: Node<T>
init() {
self.head = Node<T>()
self.tail = head
}
func isEmpty() -> Bool {
return self.count == 0
}
func push(_ value: T) {
let node = Node<T>(value: value)
if self.isEmpty() {
self.head = node
self.tail = node
} else {
node.next = self.head
self.head.prev = node
self.head = node
}
self.count += 1
}
func unshift(_ value: T) {
let node = Node<T>(value: value)
if self.isEmpty() {
self.head = node
self.tail = node
} else {
node.prev = self.tail
self.tail.next = node
self.tail = node
}
self.count += 1
}
func pop() -> T? {
if self.isEmpty() {
return nil
} else if self.count == 1 {
let temp: Node<T> = self.head
self.count -= 1
return temp.value
} else {
let temp: Node<T> = self.head
self.head = self.head.next!
self.count -= 1
return temp.value
}
}
func shift() -> T? {
if self.isEmpty() {
return nil
} else if self.count == 1 {
let temp: Node<T> = self.tail
self.count -= 1
return temp.value
} else {
let temp: Node<T> = self.tail
self.tail = self.tail.prev!
self.count -= 1
return temp.value
}
}
}
Version data entries
71 entries across 71 versions & 1 rubygems