100+ Ampcus Tech Interview Questions and Answers

Design a system similar to Gmail for sending and receiving emails.

• Use distributed systems for scalability and reliability

• Implement features like search, filters, labels, and attachments

• Utilize a database for storing emails and user data

• Include security measures like encryption and authentication

A singleton class is a class that can only have one instance created throughout the application.

• Ensure the constructor is private to prevent external instantiation.

• Provide a static method to access the single instance.

• Use lazy initialization to create the instance only when needed.

Microservices are small, independent services that work together, while monolith is a single, large application.

• Microservices are loosely coupled and can be developed, deployed, and scaled independently.

• Monoliths are tightly coupled and any change requires redeployment of the entire application.

• Microservices allow for better fault isolation and scalability.

• Monoliths are simpler to develop and deploy initially.

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

• Example...read more

Coalesce and repartition are both methods used in Pyspark for reducing the number of partitions in a DataFrame.

• Coalesce is used to reduce the number of partitions without shuffling the data, while repartition involves shuffling the data to create a specified number of partitions.

• Coalesce is more efficient when reducing the number of partitions, as it avoids shuffling the data unnecessarily.

• Repartition is useful when you need to increase the number of partitions or redistribut...read more

Spotify is a music streaming service that allows users to listen to a wide variety of songs and create personalized playlists.

• Spotify uses algorithms to recommend music based on user preferences and listening history.

• Users can create playlists, follow artists, and share music with friends.

• Spotify offers both free and premium subscription options with additional features like offline listening and ad-free music.

• The platform also includes social features like collaborative play...read more

LPS array in string refers to the Longest Palindromic Substring array in a given string.

• Create an array to store all the palindromic substrings found in the given string.

• Iterate through the string and check for palindromic substrings of different lengths.

• Store the longest palindromic substrings in the array.

DBMS is a software that manages databases, SQL is a language used to interact with databases.

• SQL stands for Structured Query Language

• SQL is used to retrieve, update, and manage data in a database

• Basic SQL commands include SELECT, INSERT, UPDATE, DELETE

• Example: SELECT * FROM table_name WHERE condition;

Train water trapping problem involves calculating the amount of water that can be trapped between blocks.

• Calculate the maximum height of blocks on left and right of each block

• Find the minimum of the two heights and subtract the height of the current block to get trapped water

• Sum up the trapped water for all blocks to get total trapped water

Use Excel's text to columns feature to split person names into separate columns.

• Select the column containing the full names

• Go to the Data tab and click on Text to Columns

• Choose 'Delimited' and select the delimiter that separates the names (e.g. space)

• Click Finish to split the names into separate columns

LRU Cache is a data structure that stores the most recently used items and discards the least recently used items when full.

• Use a combination of a doubly linked list and a hashmap to implement LRU Cache.

• Keep track of the most recently used item at the head of the linked list and the least recently used item at the tail.

• When a new item is accessed, move it to the head of the linked list and update the hashmap.

• When the cache is full, remove the tail item from the linked list an...read more

Calculate the product of all elements in an array except for the current element.

• Iterate through the array and calculate the product of all elements except the current element.

• Use two loops to calculate the product of elements before and after the current element.

• Handle edge cases like 0s in the array to avoid division by zero errors.

The rotten orange problem involves determining the minimum number of minutes it takes for all oranges to become rotten.

• Use a breadth-first search (BFS) algorithm to solve the problem

• Create a queue to store the coordinates of rotten oranges

• Iterate through the grid and enqueue all rotten oranges

• While the queue is not empty, dequeue an orange and check its neighboring oranges

• If a neighboring orange is fresh, make it rotten and enqueue its coordinates

• Keep track of the minutes pas...read more

My favorite app is Instagram, but I believe it can improve its algorithm for showing posts.

• Instagram's algorithm sometimes shows posts out of order, leading to missed content

• The explore page could be more personalized based on user interests

• There are concerns about the impact of the app on mental health due to the focus on likes and followers