Multiply two polynomials using linked list in node js

Js program for Multiply two polynomials using linked list. Here problem description and explanation.

/*
    Node JS program for
    Multiplication of two polynomials using linked list
*/
class Node
{
	constructor(data, power)
	{
		this.data = data;
		this.power = power;
		this.next = null;
	}
	// Update node value
	updateRecord(data, power)
	{
		this.data = data;
		this.power = power;
	}
}
class MultiplyPolynomial
{
	constructor()
	{
		this.head = null;
	}
	// Insert Node element
	insert(data, power)
	{
		if (this.head == null)
		{
			// Add first node
			this.head = new Node(data, power);
		}
		else
		{
			var node = null;
			var temp = this.head;
			var location = null;
			// Find the valid new node location
			while (temp != null && temp.power >= power)
			{
				location = temp;
				temp = temp.next;
			}
			if (location != null && location.power == power)
			{
				// When polynomial power already exists
				// Then add current add to previous data
				location.data = location.data + data;
			}
			else
			{
				node = new Node(data, power);
				if (location == null)
				{
					// When add node in begining
					node.next = this.head;
					this.head = node;
				}
				else
				{
					// When adding node in intermediate 
					// location or end location
					node.next = location.next;
					location.next = node;
				}
			}
		}
	}
	// Perform multiplication of given polynomial
	multiplyPolynomials(other)
	{
		// Define some useful variable
		var result = new MultiplyPolynomial();
		// Get first node of polynomial
		var poly1 = this.head;
		var temp = other.head;
		var power_value = 0;
		var coefficient = 0;
		// Execute loop until when polynomial are exist
		while (poly1 != null)
		{
			temp = other.head;
			while (temp != null)
			{
				// Get result info
				power_value = poly1.power + temp.power;
				coefficient = poly1.data * temp.data;
				result.insert(coefficient, power_value);
				// Visit to next node
				temp = temp.next;
			}
			// Visit to next node
			poly1 = poly1.next;
		}
		// return first node
		return result;
	}
	// Display given polynomial nodes
	display()
	{
		if (this.head == null)
		{
			process.stdout.write("Empty Polynomial ");
		}
		process.stdout.write(" ");
		var temp = this.head;
		while (temp != null)
		{
			if (temp != this.head)
			{
				process.stdout.write(" + " + temp.data);
			}
			else
			{
				process.stdout.write("" + temp.data);
			}
			if (temp.power != 0)
			{
				process.stdout.write("x^" + temp.power);
			}
			// Visit to next node
			temp = temp.next;
		}
		process.stdout.write("\n");
	}
}

function main()
{
	var a = new MultiplyPolynomial();
	var b = new MultiplyPolynomial();
	// Add node in polynomial A
	a.insert(9, 3);
	a.insert(4, 2);
	a.insert(3, 0);
	a.insert(7, 1);
	a.insert(3, 4);
	// Add node in polynomial b
	b.insert(7, 3);
	b.insert(4, 0);
	b.insert(6, 1);
	b.insert(1, 2);
	// Display Polynomial nodes
	console.log("\n Polynomial A ");
	a.display();
	console.log(" Polynomial B ");
	b.display();
	var result = a.multiplyPolynomials(b);
	// Display calculated result
	console.log(" Result ");
	result.display();
}
// Start program execution
main();

Output

 Polynomial A
 3x^4 + 9x^3 + 4x^2 + 7x^1 + 3
 Polynomial B
 7x^3 + 1x^2 + 6x^1 + 4
 Result
 21x^7 + 66x^6 + 55x^5 + 119x^4 + 88x^3 + 61x^2 + 46x^1 + 12