class Node {
constructor(value) {
this.value = value;
this.next = null;
}
}
class Queue {
constructor() {
this.first = null;
this.last = null;
this.length = 0;
}
peek() {
return this.first;
}
enqueue(value) {
const newNode = new Node(value);
if (this.first === null) {
this.first = newNode;
} else {
this.last.next = newNode;
}
this.last = newNode;
this.length++;
}
dequeue() {
if (this.first === null) {
return;
}
if (this.first === this.last) {
this.last = null;
}
this.first = this.first.next;
this.length--;
}
}
const myQueue = new Queue();
console.log(myQueue.peek());
myQueue.enqueue("Joy");
myQueue.enqueue("Matt");
myQueue.enqueue("Pavel");
myQueue.enqueue("Samir");
console.log(myQueue.peek());
myQueue.dequeue();
console.log(myQueue.peek());
myQueue.dequeue();
console.log(myQueue.peek());
