Summary
Although I wasn't shortlisted for the Technical Round, my Athena Health on-campus experience provided valuable insights into their assessment process, coding challenges, SQL queries, and various interview scenarios, which I believe will significantly help me in future opportunities.
Full Experience
I recently participated in Athena Health's on-campus recruitment drive. The entire process started with a Hackerrank assessment which included two coding questions, one SQL query, and four multiple-choice questions. Following this, the recruitment rounds were structured as Shortlisting, Technical Round (TR), Managerial Round (MR), and finally, HR. Regrettably, I did not make it past the shortlisting stage for the Technical Round. Despite not progressing further, I gained significant clarity on the types of questions posed in their technical, managerial, and even HR rounds, which I found to be extremely insightful and beneficial for my interview preparation.
Interview Questions (30)
Given two strings str1 and str2, check if str1 can be made equal to str2 using operations to remove the first character of str1 and insert at any position. If possible, return the minimum number of operations; else return -1.
Two strings a and b are considered matching if a can be converted to b using: Swap adjacent characters. Select substring of length k>1 with identical characters and increment all to next alphabet. Given two arrays of strings, determine for each pair whether they are matching (return 1 or 0).
Given a binary min heap 5,7,6,10,9,12,11,13, what is the level order after 2 extract-min operations?
Tables: laborers (id, name, previous_balance) and daily_hours (labor_id, entry_time, exit_time). Pay = $30 * total_hours_worked + previous_balance. Write a query to return all active employees (worked some hours), with total amount owed, sorted by name. Entry and exit times were given as VARCHAR in format YYYY-MM-DD HH:MM:SS, so I had to cast to DATETIME and use TIMESTAMPDIFF(HOUR, entry_time, exit_time).
What are the correct properties of a doubly linked list? (a) linear or circular, (b) same space as singly linked lists, (c) Needs a header. Choose the correct combination (e.g., 1) a, b; 2) b, c).
Given the merge sort code, what is its time complexity?
An employee table has 10 columns and 1 million rows, with a size of 50 MB. If a view is created with 5 columns and 1 million rows from this table, what would be the size of the view?
A coding question like Valid Parentheses was asked.
Given an integer, determine if it is a palindrome. An optimized approach was requested.
Given a set of tables, I was asked to join them based on a specific condition.
Explain Create, Read, Update, Delete (CRUD) operations.
Explain the ACID properties (Atomicity, Consistency, Isolation, Durability) in databases.
Explain the concept of Authorization.
Provide pseudocode for a sorting algorithm.
A coding question on finding the longest substring with unique characters.
Given an array of strings, check if these strings are present in a longer string.
Explain the concept of SQL Inner Join.
A logical question: three boxes are labelled incorrectly. How can you find the correctly labelled box with minimal moves?
An estimation question: how many coffee shops are in a given area, based on preference data?
Design a coffee machine using Object-Oriented Programming (OOP) principles.
Explain the difference between call by reference and call by value.
Provide an example illustrating interfaces and multiple inheritance.
Given a rotated sorted list, return the index of a specific key.
Explain the concepts of polymorphism and encapsulation in OOP.
Given an array, move all zeroes to the end of it while maintaining the relative order of the non-zero elements.
Explain and demonstrate the use of SQL GROUP BY clause with COUNT aggregate function.
Explain cache memory in a database context, including an update example.
A coding question to find the difference between two dates.
Questions about tree traversals, calculating tree height, and properties of balanced trees.
A puzzle: given 8 balls, one is heavier. Find the heavier ball using only 2 weighings.