20+ Coding Ninjas Interview Questions and Answers

JavaScript is a programming language used to create interactive web pages and web applications.

• JavaScript is used for client-side scripting, allowing for dynamic and interactive web pages.

• It can also be used for server-side scripting with Node.js.

• JavaScript is used for creating web applications, games, and mobile apps.

• It is also used for creating browser extensions and add-ons.

• JavaScript frameworks like React, Angular, and Vue.js are used for building complex web applications...read more

Yes, I am confident in my ability to solve doubts and help students understand the material.

• I have a strong understanding of the subject matter and can explain concepts clearly

• I am patient and willing to work through problems with students until they understand

• I am resourceful and can find additional materials or resources to help clarify any confusion

No, IIFE is not irreplaceable.

• There are other ways to achieve the same functionality as IIFE, such as using arrow functions or block-scoped functions.

• IIFE can also be replaced by using modules in modern JavaScript.

• However, IIFE is still a useful tool in certain situations, such as when you need to create a private scope for your code.

Find the single duplicate element in an array of strings with length n-1.

• Iterate through the array and use a HashSet to keep track of elements seen so far.

• If an element is already in the HashSet, that is the duplicate element.

• Return the duplicate element once found.

Middleware in Express is a function that has access to the request and response objects.

• Create a middleware function using app.use() method in Express.

• Middleware functions have access to the request object (req), the response object (res), and the next middleware function in the application's request-response cycle.

• Example: app.use((req, res, next) => { console.log('This is a middleware function'); next(); });

Various algorithms can be used for scheduling tasks, such as Round Robin, First Come First Serve, Shortest Job First, etc.

• Round Robin: Each task is assigned a fixed time slice, and tasks are executed in a circular manner.

• First Come First Serve: Tasks are executed in the order they arrive.

• Shortest Job First: The task with the shortest execution time is executed first.

• Priority Scheduling: Tasks are assigned priorities and executed based on their priority level.

OS stands for Operating System, which is a software that manages computer hardware and provides common services for computer programs.

• OS is the most important software that runs on a computer.

• It manages the computer's memory, processes, and all of its software and hardware.

• Examples of operating systems include Windows, macOS, Linux, and Android.

I can promote Coding Ninjas courses by organizing coding events, sharing course details on social media, and collaborating with college clubs.

• Organize coding events in college and invite Coding Ninjas as a sponsor or guest speaker

• Share course details on social media platforms like Facebook, LinkedIn, and Twitter

• Collaborate with college clubs like coding clubs, tech clubs, and entrepreneurship clubs to promote the courses

• Distribute flyers and posters in college notice boards a...read more

Lazy loading in Angular delays loading of modules until they are needed

• Lazy loading helps improve performance by only loading modules when they are required

• It is achieved by using the loadChildren property in the route configuration

• Lazy loaded modules are loaded asynchronously when the user navigates to the corresponding route

Design an order and payments system for an EdTech company

• Allow users to browse and select courses

• Implement a shopping cart for users to add courses

• Integrate payment gateways for secure transactions

• Provide order confirmation and receipt to users

• Allow users to track their order status

Server-side rendering (SSR) in Angular can be enabled by using Angular Universal.

• Install Angular Universal using Angular CLI

• Create a new Angular Universal project

• Update app.module.ts to include server-side rendering

• Build and run the Angular Universal project

JWT can be implemented by generating a token with user information and a secret key, then verifying the token using the same secret key.

• Generate a JWT token with user information and a secret key

• Include necessary claims like expiration time, issuer, etc.

• Verify the JWT token using the same secret key

• Handle token expiration and refresh if needed

Use a hash set to find duplicates in an array of strings.

• Create a hash set to store unique elements.

• Iterate through the array and check if the element is already in the hash set.

• If it is, then it is a duplicate. If not, add it to the hash set.

Throttling limits the number of times a function can be called over time, while debouncing ensures a function is only called after a certain amount of time has passed without it being called.

• Throttling limits the rate at which a function can be called, preventing it from being called more than once in a specified time frame.

• Debouncing waits for a specified amount of time to pass after the last time a function was called before actually calling it.

• Throttling is useful for limi...read more

To add one in a linked list, create a new node with the value 1 and add it to the end of the list.

• Create a new node with the value 1

• Traverse the linked list to reach the last node

• Set the next pointer of the last node to the new node

LAC stands for Location Area Code, a unique identifier for a group of cells in a mobile network.

• LAC helps in identifying the location of a mobile device within a cellular network.

• It is used for handover procedures when a device moves between different cells.

• In a network with 3 nodes, each node would have a unique LAC assigned to it.

MergeSort is a divide-and-conquer algorithm that recursively divides an array into two halves, sorts them, and then merges them.

• Divide the array into two halves

• Recursively sort each half

• Merge the sorted halves

Pollfill is a function that returns a promise which resolves when a condition is met.

• Pollfill function should return a promise

• The promise should resolve when a specific condition is met

• Use polling mechanism to check the condition at regular intervals

Reverse the order of strings in an array

• Use the reverse() method to reverse the array

• Example: ['apple', 'banana', 'cherry'] -> ['cherry', 'banana', 'apple']