Sha256: 1fba75359867612e56692fc846729805bd8b49c7905b78b1a94b71bc3b6328cd
Contents?: true
Size: 1.84 KB
Versions: 185
Compression:
Stored size: 1.84 KB
Contents
function Element(value) {
return { value, next: null, prev: null };
}
export default class Deque {
constructor() {
this.size = 0;
this.head = null;
this.tail = null;
}
pop() {
if (!this.head) {
return undefined;
}
const value = this.head.value;
if (this.head.next) {
this.head = this.head.next;
this.head.prev = null;
} else {
this.head = this.tail = null;
}
return value;
}
push(value) {
if (this.head) {
const newHead = new Element(value);
newHead.next = this.head;
this.head.prev = newHead;
this.head = newHead;
} else {
this.head = new Element(value);
this.tail = this.head;
}
}
shift() {
if (!this.tail) {
return undefined;
}
const value = this.tail.value;
if (this.tail.prev) {
this.tail = this.tail.prev;
this.tail.next = null;
} else {
this.head = this.tail = null;
}
return value;
}
unshift(value) {
if (this.tail) {
const newTail = new Element(value);
newTail.prev = this.tail;
this.tail.next = newTail;
this.tail = newTail;
} else {
this.tail = new Element(value);
this.head = this.tail;
}
}
count() {
let count = 0,
element = this.head;
while (this.head && element) {
count++;
element = element.next;
}
return count;
}
delete(value) {
let element = this.head;
while (element) {
if (element.value === value) {
if (element.next) {
element.next.prev = element.prev;
} else {
this.tail = this.tail.prev;
}
if (element.prev) {
element.prev.next = element.next;
} else {
this.head = this.head.next;
}
element = null;
} else {
element = element.next;
}
}
}
}
Version data entries
185 entries across 185 versions & 1 rubygems