LinkedList in real time

A LinkedList is basically a data structure which contains information which are linked with each other.

From programmer point of view - A Linkedlist contains multiple values and every value contains a data and reference to next value.

Linkedlist can be used to implement queue or stack basically linear storage.

In this article- i am going to create a storage wrapper which will use linkedList to store data & perform some functionalities -

We will be doing -

• Storing value in sorted order
• printing stored value
• Checking if value exist

Let’s Code

First we will write program to store value in linked list -

class Storage {
    constructor() {
        this.root = null;
    }
    getNewNode(data) {
        return {
            data: data,
            next: null
        }
    }
    add(data) {
        const node = this.getNewNode(data);
        let root = this.root;
        if (root == null) {
            this.root = node;
        } else {
            while (root.next != null) {
                root = root.next;
            }
            root.next = node;
        }
    }
   printAll(){
       let root = this.root;
       while(root!=null){
         console.log(root.data);
         root = root.next;   
       }
    }
}
const myStorage = new Storage();
myStorage.add(5);
myStorage.add(51);
myStorage.add(15);
myStorage.printAll();

The above code only store the data but not in ordered way. Let’s see how we can store the data in ordered way.

Store in ordered way

class Storage{
    
    constructor(){
        this.root=null;
    }
    
    getNewNode(value){
        return {
            data:value,
            next:null
        }
    }
   compareAndstoreInSortedOrder(newNode, root){
       const value = newNode.data;
       if(root.data>value){
          const next = root.next;
          newNode.data = root.data;
          root.data = value;
          root.next = newNode;
          newNode.next = next;
      }
    }
    
    add(value){
        let root = this.root;
        let newNode = this.getNewNode(value);
        if(root==null){
            this.root = newNode;
        }
        else if(root.next==null && root.data> newNode.data){
          this.compareAndstoreInSortedOrder(newNode,root);
        }
        else{
            while(root.next!=null){
                console.log("root", root.data, value);
                this.compareAndstoreInSortedOrder(newNode,root);
                root = root.next;
            }
            root.next = newNode;
        }
    }
    printAll(){
       let root = this.root;
       while(root!=null){
         console.log(root.data);
         root = root.next;   
       }
    }
}
const store = new Storage();
store.add(5);
store.add(3);
store.add(10);
store.printAll();

Check if value exist

class Storage{
    
    constructor(){
        this.root=null;
    }
    
    getNewNode(value){
        return {
            data:value,
            next:null
        }
    }
   compareAndstoreInSortedOrder(newNode, root){
       const value = newNode.data;
       if(root.data>value){
          const next = root.next;
          newNode.data = root.data;
          root.data = value;
          root.next = newNode;
          newNode.next = next;
      }
    }
    
    add(value){
        let root = this.root;
        let newNode = this.getNewNode(value);
        if(root==null){
            this.root = newNode;
        }
        else if(root.next==null && root.data> newNode.data){
          this.compareAndstoreInSortedOrder(newNode,root);
        }
        else{
            while(root.next!=null){
                console.log("root", root.data, value);
                this.compareAndstoreInSortedOrder(newNode,root);
                root = root.next;
            }
            root.next = newNode;
        }
    }
    printAll(){
       let root = this.root;
       while(root!=null){
         console.log(root.data);
         root = root.next;   
       }
    }
    isExist(value){
       let root = this.root;
       do{
          if(root.data===value){
             return true;
          }
          root = root.next;
       }while(root!=null);
       return false;
    }
}
const store = new Storage();
store.add(5);
store.add(3);
store.add(10);
store.isExist(3) // true
store.isExist(9) // false