class Node {
constructor(value){
this.value = value;
this.next = null;
}
}
class Queue {
constructor(){
this.top = null;
this.bottom = null;
this.length = 0
}
peek(){
return this.top.value
}
enqueue(value){
if(!value) return
const newNode = new Node(value)
if(this.length === 0){
this.top = newNode
this.bottom = newNode
}else{
this.bottom.next = newNode;
this.bottom = newNode;
}
this.length++
return this
}
empty(){
return this.length === 0
}
dequeue(){
if(this.length === 0) return
if(this.length === 1){
this.bottom = null;
}
let currentItem = this.top
this.top = this.top.next;
this.length--;
return currentItem.value
}
}
const queue = new Queue();
queue.enqueue("1")
console.log(queue)
queue.enqueue("2")
console.log(queue)
console.log(queue.dequeue())
queue.enqueue("5")
console.log(queue.dequeue())
console.log(queue.peek())
