strategies to reverse a linked list in JavaScript

Question

I just struggled through a simple interview question: Please reverse a singly linked list.

While I failed to provide a working answer in time to save the interview,

Answer 1

//O(n) | O(1) wherre n is the number of nodes in the linked list

class Node{
  constructor(val){
    this.val = val;
    this.next = null;
  }
}


function reverseLinkedList(head) {

 if(!head) return null;
 
 let p1 = head;
 let p2 = null;
	
	while(p1){
		let temp = p1.next;
		p1.next = p2;
		p2 = p1;
		p1 = temp;
	}
	
	return p2;
}


const a = new Node(1);
a.next = new Node(2);
a.next.next = new Node(3)

console.log("Current Node",a);
console.log("Reversed List",reverseLinkedList(a))