Javascript Program For Comparing Two Strings Represented As Linked Lists

Given two strings, represented as linked lists (every character is a node in a linked list). Write a function compare() that works similar to strcmp(), i.e., it returns 0 if both strings are the same, 1 if the first linked list is lexicographically greater, and -1 if the second string is lexicographically greater.
Examples:

Input: list1 = g->e->e->k->s->a
       list2 = g->e->e->k->s->b
Output: -1

Input: list1 = g->e->e->k->s->a
       list2 = g->e->e->k->s
Output: 1

Input: list1 = g->e->e->k->s
       list2 = g->e->e->k->s
Output: 0

Javascript

<script>
// Javascript program to compare two
// strings represented as a linked list

// Linked List Class

// head of list
var head;
var a, b;

// Node Class
class Node
{
    // Constructor to create a
    // new node
    constructor(d)
    {
        this.data = d;
        this.next = null;
    }
}

function compare(node1, node2)
{
    if (node1 == null &&
        node2 == null)
    {
        return 1;
    }

    while (node1 != null &&
           node2 != null &&
           node1.data == node2.data)
    {
        node1 = node1.next;
        node2 = node2.next;
    }

    // If the list are different
    // in size
    if (node1 != null &&
        node2 != null)
    {
        return (node1.data >
                node2.data ? 1 : -1);
    }

    // If either of the list has
    // reached end
    if (node1 != null &&
        node2 == null)
    {
        return 1;
    }

     if (node1 == null &&
         node2 != null)
     {
         return -1;
     }
     return 0;
}

// Driver code
var result = null;
a = new Node('g');
a.next = new Node('e');
a.next.next = new Node('e');
a.next.next.next =
new Node('k');
a.next.next.next.next =
new Node('s');
a.next.next.next.next.next =
new Node('b');

b = new Node('g');
b.next = new Node('e');
b.next.next = new Node('e');
b.next.next.next =
new Node('k');
b.next.next.next.next =
new Node('s');
b.next.next.next.next.next =
new Node('a');

var value;
value = compare(a, b);
document.write(value);
// This code is contributed by gauravrajput1
</script>

Output:

1

Time Complexity: O(M + N), where M and N represents the length of the given two linked lists.
Auxiliary Space: O(1), no extra space is required, so it is a constant.

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