Firepro Systems Interview Questions and Answers

Count occurrences of two nodes with same horizontal distance in a binary tree

• Traverse the tree using BFS or DFS and keep track of horizontal distance of each node

• Store nodes with same horizontal distance in a hash table and increment count if collision occurs

• Recursively traverse left and right subtrees with updated horizontal distance

• Time complexity: O(n), Space complexity: O(n)

Check if any 3 elements in an array add up to a given number

• Sort the array in ascending order

• Use nested loops to iterate through all possible combinations of 3 elements

• Check if the sum of the 3 elements equals the given number

• Return true if a match is found, else false

Considerations for developing an application for computer aided competitive exams

• User-friendly interface for easy navigation

• Accurate and reliable question bank

• Timed tests to simulate real exam conditions

• Option to save and resume tests

• Detailed performance analysis and feedback

• Compatibility with different devices and operating systems

• Regular updates and bug fixes

• Developer should consider the security of the application to prevent cheating

• User perspective: The application should...read more

Reverse every 3 nodes in a singly linked list using recursion

• Create a recursive function that takes in a node and a count

• If count is less than 3, return the node

• Reverse the first 3 nodes and call the function recursively with the 4th node and count 1

• Connect the reversed nodes to the rest of the list

• Return the new head of the reversed list

Test methods for stress testing of Furniture class

• Create a large number of Furniture objects and check for memory leaks

• Simulate heavy usage by continuously calling methods and check for performance issues

• Test the Furniture class with maximum allowed input values and check for any errors or crashes

Program to check if a linked list is a palindrome

• Traverse the linked list and push each element onto a stack

• Traverse the linked list again and compare each element with the top of the stack

• If all elements match, the linked list is a palindrome