Javascript Program For Sorting Linked List Which Is Already Sorted On Absolute Values

// Javascript program to sort a linked list, 
// already sorted by absolute values

// head of list
let head;

// Linked list Node 
class Node {
    constructor(d) {
        this.data = d;
        this.next = null;
    }
}

// To sort a linked list by actual values.
// The list is assumed to be sorted by 
// absolute values.
function sortedList(head) {
    // Initialize previous and current 
    // nodes
    let prev = head;
    let curr = head.next;

    // Traverse list
    while (curr != null) {
        // If curr is smaller than prev, then
        // it must be moved to head
        if (curr.data < prev.data) {
            // Detach curr from linked list
            prev.next = curr.next;

            // Move current node to beginning
            curr.next = head;
            head = curr;

            // Update current
            curr = prev;
        }

        // Nothing to do if current element
        // is at right place
        else
            prev = curr;

        // Move current
        curr = curr.next;
    }
    return head;
}

/* Inserts a new Node at front of 
   the list. */
function push(new_data) {
    /* 1 & 2: Allocate the Node & 
              Put in the data */
    let new_node = new Node(new_data);

    // 3. Make next of new Node as head 
    new_node.next = head;

    // 4. Move the head to point to 
    // new Node 
    head = new_node;
}

// Function to print linked list 
function printList(head) {
    let temp = head;
    while (temp != null) {
        console.log(temp.data);
        temp = temp.next;
    }
}

// Driver code  
/* Constructed Linked List is
   1->2->3->4->5->6-> 7->8->8->
   9->null */
push(-5);
push(5);
push(4);
push(3);
push(-2);
push(1);
push(0);
console.log("Original List :");
printList(head);
head = sortedList(head);
console.log("Sorted list :");
printList(head);
// This code is contributed by aashish1995