FourCore Interview Questions and Answers

Sort employees by salary and department

• Create a comparator function to compare salary and department

• Use the comparator function with the sort() method on the employee stream

• Return the sorted employee stream

Program to find 2nd largest number in array

• Sort the array in descending order and return the 2nd element

• Initialize two variables, largest and secondLargest, and iterate through the array to find the two largest numbers

• Use a priority queue to keep track of the two largest numbers

To check if a linkedlist is palindrome or not

• Traverse the linkedlist and push each element into a stack

• Traverse the linkedlist again and compare each element with the popped element from the stack

• If all elements match, then the linkedlist is palindrome

I primarily use the MVC design pattern for its clear separation of concerns and ease of maintenance.

• MVC (Model-View-Controller) - separates data, presentation, and user input into three interconnected components

• Singleton - ensures a class has only one instance and provides a global point of access to it

• Factory - creates objects without specifying the exact class of object that will be created

• Observer - defines a one-to-many dependency between objects so that when one object c...read more

Program to find the prefix of OL in an array of strings

• Loop through each string in the array

• Check if the first two characters are 'OL'

• If yes, add the string to a new array of prefixes

• Return the array of prefixes

Count duplicates in array of strings

• Create a dictionary to store the count of each string

• Loop through the array and increment the count in dictionary

• Loop through the dictionary and count the duplicates

• Return the count of duplicates

Design a Parking Management System for efficient parking space allocation and management.

• Implement a system to track available parking spaces in real-time.

• Include features for booking parking spots in advance.

• Incorporate a payment system for parking fees.

• Utilize sensors or cameras for monitoring parking space occupancy.

• Develop a user-friendly interface for customers to easily navigate and use the system.