Coding Interview Preparation

JavaScript Coding Interview Questions Easy 1. Find the second smallest number in an array. 2. Reverse the order of words in a sentence. 3. Check whether a string starts and ends with the same character. 4. Find the average of numbers in an array. 5. Find all numbers that appear more than once in an array. 6. Replace every space in a string with a hyphen. 7. Find the longest common prefix among an array of strings. 8. Check whether an array is sorted in ascending order. 9. Find the index of the first occurrence of a given value without using indexOf(). 10. Separate even and odd numbers into two arrays. 11. Find the difference between the largest and smallest values in an array. 12. Remove a specific element from an array without using filter(). 13. Convert an array of numbers into an array of their squares. 14. Find the number of words in a sentence. 15. Swap two variables without using a temporary variable. Medium 16. Implement a function that converts a nested object into a flat object. 17. Create a function that groups an array of objects by multiple properties. 18. Implement a function that removes duplicate objects from an array based on a property. 19. Write a function that compares two arrays regardless of their order. 20. Implement a custom version of Array.prototype.find(). 21. Implement a custom version of Array.prototype.some(). 22. Implement a custom version of Array.prototype.every(). 23. Create a function that splits an array into chunks of a given size. 24. Implement a function that shuffles an array fairly. 25. Create a countdown timer using setInterval(). 26. Implement a timeout wrapper for a Promise. 27. Write a function that caches the result of asynchronous operations. 28. Create a function that executes asynchronous tasks sequentially. 29. Implement a simple rate limiter for function calls. 30. Write a function that waits for multiple Promises but returns only the successful results. 31. Implement a custom deep-equality function for JavaScript objects. 32. Create a function that detects whether two strings are rotations of each other. 33. Implement a function that converts a JavaScript object into FormData. 34. Create a search function that filters and ranks objects based on a user's query. Hard 35. Implement a simplified version of Promise.any(). 36. Build a priority queue using JavaScript classes. 37. Implement a trie data structure for autocomplete. 38. Build a dependency resolver that determines the correct execution order of tasks. 39. Implement a simplified JavaScript module system with import and export behavior. 40. Build a worker pool that limits how many asynchronous tasks can run at the same time.