Senior Software Developer 2 Interview Questions and Answers

Topological sort is a linear ordering of vertices in a directed acyclic graph. Counting number of islands involves identifying connected components in a graph.

• Topological sort is used to order vertices in a graph such that for every directed edge uv from vertex u to vertex v, u comes before v in the ordering.

• Number of islands in a graph can be counted by performing a depth-first search (DFS) or breadth-first search (BFS) to identify connected components.

• For example, in a grid...read more

Microservices pattern is an architectural style that structures an application as a collection of small, independent services.

• Microservices are independently deployable and scalable.

• Each microservice focuses on a specific business capability.

• Communication between microservices is usually done through APIs.

• Microservices can be developed using different programming languages and technologies.

• Examples of companies using microservices include Netflix, Amazon, and Uber.

Twitter's high level system design involves multiple services like user management, tweet storage, timeline generation, and real-time notifications.

• Use microservices architecture for scalability and fault tolerance

• Store user data in a distributed database like Cassandra or MongoDB

• Use a message queue like Kafka for real-time notifications

• Implement a caching layer for frequently accessed data like timelines

• Use a load balancer to distribute traffic evenly across servers

OOPS concepts are fundamental principles in object-oriented programming, including inheritance, encapsulation, polymorphism, and abstraction.

• Inheritance: Allows a class to inherit properties and behavior from another class. Example: Animal class can be inherited by Dog class.

• Encapsulation: Bundling data and methods that operate on the data into a single unit. Example: Using private variables and public methods in a class.

• Polymorphism: Ability of a function to behave different...read more

Binary search is a divide and conquer algorithm that efficiently finds the target value within a sorted array.

• Divide the array in half and compare the target value to the middle element

• If the target value is less than the middle element, search the left half of the array

• If the target value is greater than the middle element, search the right half of the array

• Repeat the process until the target value is found or the subarray is empty

Find the maximum sum of a subarray within an array of integers.

• Use Kadane's algorithm to find the maximum sum subarray in O(n) time complexity.

• Initialize max_sum and current_sum variables to track the maximum sum subarray.

• Iterate through the array and update current_sum by adding the current element or starting a new subarray.

• Update max_sum if current_sum is greater than max_sum.

• Return max_sum as the result.

Garbage collection in C# manages memory automatically by reclaiming unused memory.

• Garbage collection in C# uses different algorithms like Mark and Sweep, Reference Counting, and Generational.

• It helps in preventing memory leaks and improves performance by automatically releasing memory.

• Developers can also force garbage collection using System.GC.Collect() method.

• Example: var obj = new Object(); obj = null; // Garbage collector will reclaim memory for obj.