class Node { constructor(val) { this.val = val; this.next = null; } } class SinglyLinkedList { constructor() { this.head = null; this.tail = null; this.length = 0; } push(val) { var newNode = new Node(val); if (!this.head) { this.head = newNode; this.tail = this.head; } else { this.tail.next = newNode; this.tail = newNode; } this.length++; return this; } pop() { if (!this.head) return undefined; var current = this.head; var newTail = current; while (current.next) { newTail = current; current = current.next; } this.tail = newTail; this.tail.next = null; this.length--; if (this.length === 0) { this.head = null; this.tail = null; } return current; } shift() { if (!this.head) return undefined; var currentHead = this.head; this.head = currentHead.next; this.length--; if (this.length === 0) { this.tail = null; } return currentHead; } unshift(val) { var newNode = new Node(val); if (!this.head) { this.head = newNode; this.tail = this.head; } newNode.next = this.head; this.head = newNode; this.length++; return this; } get(index) { if (index < 0 || index >= this.length) return null; var counter = 0; var current = this.head; while (counter !== index) { current = current.next; counter++; } return current; } set(index, val) { var foundNode = this.get(index); if (foundNode) { foundNode.val = val; return true; } return false; } insert(index, val) { if (index < 0 || index > this.length) return false; if (index === this.length) return !!this.push(val); if (index === 0) return !!this.unshift(val); var newNode = new Node(val); var prev = this.get(index - 1); var temp = prev.next; prev.next = newNode; newNode.next = temp; this.length++; return true; } remove(index) { if (index < 0 || index >= this.length) return undefined; if (index === 0) return this.shift(); if (index === this.length - 1) return this.pop(); var previousNode = this.get(index - 1); var removed = previousNode.next; previousNode.next = removed.next; this.length--; return removed; } reverse() { var node = this.head; this.head = this.tail; this.tail = node; var next; var prev = null; for (var i = 0; i < this.length; i++) { next = node.next; node.next = prev; prev = node; node = next; } return this; } print() { var arr = []; var current = this.head; while (current) { arr.push(current.val); current = current.next; } console.log(arr); } } var list = new SinglyLinkedList(); list.push(100); list.push(201); list.push(250); list.push(350); list.push(999); list.print();