Nykaa Senior Android Developer Interview Questions and Answers

Q1. Lazy vs latinit
Ans. 
lazy vs lateinit are both used in Kotlin to delay the initialization of variables, but lazy is for val properties and lateinit is for var properties.
• lazy is a property delegate that initializes the value only upon first access

• lateinit is used for var properties that are guaranteed to be initialized before accessing them

• lazy can be used for properties that are computationally expensive to initialize, while lateinit is u...read more
Answered by AI
Add your answer
Q2. Hashmap vs hashtable
Add your answer

Q1. Lifecycle questions
Add your answer
Q2. Java vs kotlin
Ans. 
Kotlin is a modern, concise language that enhances Android development, while Java is a long-established, widely-used programming language.
• Kotlin is more concise than Java, reducing boilerplate code. Example: data classes in Kotlin require less code than Java POJOs.

• Kotlin supports null safety, reducing NullPointerExceptions. Example: 'var name: String?' allows null values, while 'var name: String' does not.

• Kotlin has e...read more
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Easy

This round was held during university hours and consisted of 2 coding questions.

Round duration - 120 minutes
Round difficulty - Easy

Make sure you do no cutting and are clear about the approach you'd be following. 
 

Q1. What is the running median of an input stream?
Ans. 
Running median of an input stream is the median value of the numbers seen so far in a continuous stream of data.
• Maintain two heaps - a max heap for the lower half of the numbers and a min heap for the upper half.

• Keep the number of elements in the two heaps balanced or differ by at most 1.

• If the total number of elements is odd, the median is the root of the max heap. If even, it is the average of the roots of the two he...read more
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Easy

Two coding questions were given in the first round to be solved in 60 minutes.

Q1. 
Rearrange Array Elements Problem Statement
Given an array A containing 'N' integers and an integer m, rearrange the elements of the array such that the differences between the array elements and m are sor...read more
Ans. 
Rearrange array elements based on their differences from a given integer.
• Calculate the differences between each element and the given integer.

• Sort the elements based on their differences while maintaining the original order for elements with the same difference.

• Implement a function to rearrange the array elements as per the given criteria.
Answered by AI
Add your answer
Q2. 
Print Nodes at Distance K from a Given Node
Given an arbitrary binary tree, a node of the tree, and an integer 'K', find all nodes that are at a distance K from the specified node, and return a list of th...read more
Ans. 
The task is to find all nodes in a binary tree that are at a distance K from a given node.
• Traverse the binary tree to find the given node

• From the given node, perform a depth-first search to find all nodes at distance K

• Use a list to store the values of the nodes at distance K

• Return the list of values in any order
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Easy

This was a technical round with questions based on DSA, DBMS, Computer Networking and project based questions.

Q1. 
Triangle of Numbers Pattern
Ninja is tasked with printing a triangle pattern based on a given number 'N' for any test case.
Example:
Input:
N = 4
Output:
   1
  232
 34545
4567654
Explanation:
The pat...read more
Ans. 
Print a triangle pattern of numbers based on a given number 'N'.
• Iterate through each row and print the numbers accordingly

• Use spaces to center-align the numbers in each row

• Increment the numbers in each row as per the pattern
Answered by AI
Add your answer
Q2. What is the difference between a web server and an application server?
Ans. 
Web server serves static content over HTTP, while application server runs dynamic content and business logic.
• Web server handles HTTP requests and responses, serving static content like HTML, images, and CSS.

• Application server executes business logic, runs dynamic content, and interacts with databases.

• Web server examples include Apache, Nginx, while application server examples include Tomcat, JBoss.

• Web server focuses on...read more
Answered by AI
Add your answer
Q3. How does the internet work?
Ans. 
The internet is a global network of interconnected computers that communicate using standardized protocols.
• The internet is made up of a vast number of interconnected networks of computers.

• Data is transmitted over the internet using protocols such as TCP/IP.

• Websites are hosted on servers connected to the internet, and users access them using web browsers.

• Internet Service Providers (ISPs) provide access to the internet f...read more
Answered by AI
Add your answer
Q4. Write a SQL query to find the nth highest salary.
Ans. 
SQL query to find the nth highest salary
• Use the 'SELECT DISTINCT' statement to get unique salary values

• Order the salaries in descending order using 'ORDER BY' clause

• Use 'LIMIT' and 'OFFSET' to get the nth highest salary
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Easy

Typical HR round with behavioral problems.