CSM Technologies Senior Software Engineer Interview Questions and Answers

Event loop is a mechanism that allows non-blocking I/O operations in a single-threaded environment.

• Event loop is used in programming languages like JavaScript and Python.

• It manages the execution of multiple tasks by prioritizing them based on their priority level.

• It continuously checks for new events and executes them in a loop.

• It allows for efficient handling of I/O operations without blocking the main thread.

• It is co...read more

let, var and const are used to declare variables in JavaScript with different scoping rules and mutability.

• let and var are used to declare variables that can be reassigned later, but var has function scope while let has block scope.

• const is used to declare variables that cannot be reassigned and have block scope.

• Using const does not mean the value is immutable, only the variable reference is.

• let and const were introduc...read more

Remove duplicate entries from array of strings using JavaScript

• Use Set to remove duplicates

• Convert Set back to array

• Use spread operator to convert Set to array

Determines if words in given array are anagram or not using JS

• Create a function that takes an array of strings as input

• Loop through the array and sort each string alphabetically

• Compare the sorted strings to check if they are equal

• Return true if all strings are anagrams, else false

Creating a reusable modal component in React JS with accessibility and styling considerations.

• Use functional components and hooks for state management.

• Implement props for dynamic content: <Modal title='My Modal' content='Hello World' />.

• Add a backdrop for better user experience and to focus on the modal.

• Include keyboard accessibility: close modal on 'Escape' key press.

• Style the modal using CSS or a CSS-in-JS libr...read more

Implementing a custom version of Array.map to transform array elements.

• Define a function that takes a callback and an array as arguments.

• Use a for loop to iterate over the array elements.

• Apply the callback to each element and push the result to a new array.

• Return the new array after the loop completes.

• Example: const myMap = (arr, callback) => { /* implementation */ };