AthenaHealth Interview Experience (On - Campus)

Round 1 at AthenaHealth: Hakerrank - 12 Questions - 90 mins  

10 MCQ: Based on core subjects like OS, CN, and OOPS concepts. Also, Code related questions to predict the output of the given code.

2 Coding Questions:

1. Profit Target: Given an array of n elements where each element gives the yearly profit of a corresponding stock, find the max number of distinct pairs (pairs differing in at least one element) from the array that adds up to the given profit target. Sample Input 1:

   [1,3,46,1,3,9] , sum = 47
   possible pairs are: (1,46), (46,1), (46,1), (1,46) 
   indexes: [0][2] [2][0] [2][3] [3][2]
    - four times due to repetition of '1'
    - return only once - (46,1)
   Hence, output = 1

   Sample Input 2:

   [5,7,9,13,11,6,6,3,3] sum = 12
   possible pairs are: (5,7), (7,5), (9,3), 
    (9,3), (3,9), (9,3),
    (6,6), (6,6)
   indexes: [0][1] [1][0] [2][7] [2][8] 
    [7][2] [8][2] [5][6] [6][5]
    return only distinct - (5,7), (9,3), (6,6)
    Hence, output = 3

2. Simple Max Difference: Given an array of size n where elements are closing prices of a particular stock on n days in order, find the maximum profit spread of the stock. Profit spread it the difference between the closing price of a day and the closing price on any of the previous days in history. If the prices remain flat or are continuously decreasing, return -1. Sample input 1:

   [7,1,2,5] 
    1<7 -> continue;
    2>1 -> 2-1 = 1 : diff
    5>2 -> 5-2 = 3
    5-1 = 4 : maximum diff = output

   Sample Input 2:

   [7,5,2,1]
    5<7 , 2<5 , 1<2 -> continuously decreasing : return -1;

Round 2: Technical Interview on Hakerrank CodePair - 60 mins

1. Based on projects - Blockchain
   • What is blockchain?
   • How is it useful?
   • How does it ensure data confidentiality and integrity
   • Explain its working.
2. Based on projects - MEAN Stack
   • What did you do?
   • What is mongo?
   • What do you know about nonstructural databases?
3. Based on programming languages - C, C++, Java
   • What is the difference between C, C++, and Java?
   • What are object-oriented and procedural languages?
   •  Is java a true object-oriented language? Is C++? Explain.
   •  If yes, then how does java use primitive data types like int and char?
   •  What is the difference between Integer Class and int data type?
   •  For particular application development, how would you choose between C++ and Java  
   • What constraints would you focus on for the selection?
   • What are pointers and how is the memory allocated for them?
   • What is the problem with pointers - why were they removed when java was built?
   • What are the Object-oriented concepts?
   • Explain the difference between Encapsulation and Abstraction
   • What is Inheritance?
   • What are the types of inheritance?
   • Do we need to explicitly call the parent class constructor from the child class constructor?
   • Does C++ support all types of inheritance? Does Java support all?
   • How are multiple inheritances handled in C++?
   • What is method overriding and overloading?
   • Give a real-life example of function overloading and overriding?
   • Can Static variables in a class be accessed by the child classes that inherit it?
   • What is the memory architecture in C++ Programming? - regarding heap, stack, and code
   • If the stack is increased indefinitely due to the number of recursion calls, will it override the heap?
   • Difference between String and StringBuilder classes? What is the use of StringBuilder?
4. Coding problem  
   • Implement Merge Sort
   • Show Inheritance using abstract class

Round 3: HR - Basic behavioral questions.