Cyanous Software Interview Questions and Answers

HashMap is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values based on keys.

• HashMap internally uses an array of linked lists to store key-value pairs.

• When a key-value pair is added, the key is hashed to determine the index in the array where it will be stored.

• If multiple keys hash to the same index, a linked list is used to handle collisions.

• To retrieve a value, the key is hash...read more

Find anagrams from a string array

• Iterate through each string in the array

• Sort the characters of each string to create a key for comparison

• Use a hashmap to group anagrams together

• Return the grouped anagrams as arrays

A top view of a binary tree shows the nodes visible when looking at the tree from the top.

• The top view of a binary tree is the set of nodes visible when looking at the tree from the top.

• Nodes at the same horizontal distance from the root are considered at the same level.

• Use a map to store the horizontal distance of each node and only keep the first node encountered at each horizontal distance.

Height of a binary tree is the maximum number of edges on the longest path from the root node to a leaf node.

• Height of an empty tree is -1

• Height of a tree with only one node is 0

• Height of a binary tree can be calculated recursively by finding the height of left and right subtrees and adding 1 to the maximum of the two heights

Factory pattern creates objects without exposing the instantiation logic, while Abstract Factory pattern provides an interface for creating families of related objects.

• Factory pattern is a creational design pattern that provides a way to create objects without specifying the exact class of object that will be created.

• Abstract Factory pattern is a creational design pattern that provides an interface for creating familie...read more

Design a scalable system for millions of users

• Use microservices architecture to break down the system into smaller, independent services

• Implement load balancing to distribute traffic evenly across servers

• Utilize caching mechanisms to reduce database load and improve performance

• Use horizontal scaling by adding more servers to handle increased traffic

• Implement monitoring and alerting systems to track system performance a

Kafka implementation in Spring Boot allows for easy integration of Kafka messaging system in Java applications.

• Use Spring Kafka to configure Kafka properties in Spring Boot application

• Create Kafka producer and consumer beans to send and receive messages

• Use @KafkaListener annotation to listen for messages on specific topics

Kafka deletes messages based on retention policies and compaction

• Kafka deletes messages based on retention policies set at topic level

• Messages can also be deleted through log compaction process

• Retention policies can be based on time or size of messages

Kafka configuration involves setting up properties like broker, topic, partitions, replication factor, etc.

• Configure Kafka broker properties in server.properties file

• Create topics using kafka-topics.sh script

• Set up partitions and replication factor for fault tolerance

• Adjust consumer and producer configurations as needed

Structured logs have a predefined format for easy parsing, while unstructured logs do not.

• Structured logs are easier to search, filter, and analyze compared to unstructured logs.

• Unstructured logs can be harder to parse and may require more manual effort to extract useful information.

• Examples of structured logs include JSON or CSV format, while unstructured logs may be plain text or free-form messages.

Microservices communicate through lightweight protocols like HTTP, messaging queues, and RPC.

• Microservices can communicate over HTTP using RESTful APIs.

• Message queues like RabbitMQ or Kafka can be used for asynchronous communication between microservices.

• Remote Procedure Calls (RPC) can be used for synchronous communication between microservices.

• Service discovery mechanisms like Eureka or Consul help microservices loca...read more

I chose this company because of its innovative projects, strong team culture, and opportunities for growth.

• Innovative projects that challenge me to learn and grow

• Strong team culture that fosters collaboration and support

• Opportunities for career growth and advancement

Seeking new challenges and growth opportunities in a dynamic environment.

• Looking to expand skill set and knowledge in Java development

• Interested in working on innovative projects and technologies

• Seeking a more collaborative and supportive work culture

Handling difficult situations by staying calm, analyzing the problem, and finding a solution.

• Remaining calm under pressure

• Identifying the root cause of the problem

• Collaborating with team members to brainstorm solutions

• Prioritizing tasks to address the issue efficiently