10+ Maa Sharda College of Nursing & Paramedical Sciences Interview Questions and Answers

Find the repeated and missing element in an array of n elements containing 0 to n-1 elements.

• Create a hash table to keep track of the frequency of each element.

• Iterate through the array and update the hash table.

• Find the element with frequency greater than 1 as the repeated element.

• Find the missing element by subtracting the sum of array elements from the sum of 0 to n-1 elements.

• Return the repeated and missing elements.

React is more lightweight and flexible than Angular, making it ideal for smaller projects or those with less complex requirements.

• React is easier to learn and use than Angular, making it more accessible to developers of all skill levels.

• React's virtual DOM allows for faster rendering and better performance than Angular's two-way data binding.

• React's component-based architecture makes it easier to reuse code and maintain consistency across a project.

• React has a larger and more...read more

Reconciliation process is used by React to update the DOM efficiently.

• Reconciliation is the process of comparing the new virtual DOM with the previous one to identify the changes.

• React then updates only the necessary changes to the real DOM, instead of re-rendering the entire page.

• This process helps in improving the performance of the application.

• React uses a diffing algorithm to compare the two virtual DOMs and identify the changes.

• The diffing algorithm is optimized to reduc...read more

A website gets loaded on the browser through a series of steps including DNS resolution, HTTP request, server response, rendering, and scripting.

• The browser sends a DNS request to resolve the website's domain name to an IP address.

• The browser sends an HTTP request to the server for the website's resources.

• The server responds with the requested resources, including HTML, CSS, JavaScript, and media files.

• The browser renders the HTML and CSS to display the website's content.

• The ...read more

React has three main life cycle methods: Mounting, Updating, and Unmounting.

• Mounting: constructor(), static getDerivedStateFromProps(), render(), componentDidMount()

• Updating: static getDerivedStateFromProps(), shouldComponentUpdate(), render(), getSnapshotBeforeUpdate(), componentDidUpdate()

• Unmounting: componentWillUnmount()

• Examples: componentDidMount() is used to fetch data from an API, componentWillUnmount() is used to clean up any resources used by the component before it ...read more

A stateful functional component can be created using the useState hook in React.

• Import the useState hook from React

• Declare a state variable using the useState hook

• Use the state variable in the component

• Update the state variable using the setState function

• Example: const [count, setCount] = useState(0);

• Example: setCount(count + 1)}>Click me

Shadowing in JavaScript is when a variable declared within a certain scope has the same name as a variable in an outer scope.

• Occurs when a variable in a local scope has the same name as a variable in a parent scope

• The local variable takes precedence over the parent variable within the local scope

• Can cause confusion and unexpected behavior if not handled properly

React component life cycle defines the stages of a component from initialization to destruction.

• React component life cycle consists of three phases: Mounting, Updating, and Unmounting.

• Mounting phase includes constructor, getDerivedStateFromProps, render, componentDidMount methods.

• Updating phase includes getDerivedStateFromProps, shouldComponentUpdate, render, getSnapshotBeforeUpdate, componentDidUpdate methods.

• Unmounting phase includes componentWillUnmount method.

• Life cycle m...read more

Floating point arithmetic is not exact, hence 0.1+0.2 may not be exactly 0.3.

• Floating point numbers are represented in binary, which can lead to rounding errors.

• 0.1 and 0.2 cannot be represented exactly in binary, hence the result may not be exact.

• This is not specific to JavaScript, but a general issue with floating point arithmetic.

• To avoid such issues, use libraries like decimal.js or round off the result to a certain number of decimal places.