10+ Prologic Web Solutions Interview Questions and Answers

Implement a function to find square root of a number with specified decimal precision.

• Implement a function that takes two integers N and D as input and returns the square root of N with precision up to D decimal places.

• Ensure that the discrepancy between the computed result and the correct value is less than 10^(-D).

• Handle multiple test cases efficiently within the given constraints.

• Consider using mathematical algorithms like Newton's method for square root calculation.

• Test t...read more

Perform vertical order traversal of a binary tree based on decreasing 'Y' coordinates.

• Implement a function to perform vertical order traversal of a binary tree

• Nodes are added in order from top to bottom based on decreasing 'Y' coordinates

• Handle cases where two nodes have the same position by adding the node that appears first on the left

Calculate x raised to the power of n, accepting x and n as input and displaying the result.

• Accept two integers x and n as input

• Compute x^n and display the result

• Handle special case 0^0 = 1

• Ensure x is between 0 and 8, and n is between 0 and 9

Find the length of the longest substring with unique characters in a given string.

• Use a sliding window approach to keep track of the longest substring without repeating characters.

• Use a hashmap to store the index of each character in the string.

• Update the start index of the window when a repeating character is encountered.

• Calculate the maximum length of the window as you iterate through the string.

• Return the maximum length as the result.

Convert a given string into a zig-zag pattern on a specified number of rows and output the result row-wise.

• Iterate through the string and place characters in the zig-zag pattern based on the row number

• Keep track of the direction of movement (up or down) to determine the row placement

• Combine characters from each row to get the final result

The architecture of our current project is a microservices-based system with a combination of RESTful APIs and message queues.

• Utilizes microservices architecture for scalability and flexibility

• Uses RESTful APIs for communication between services

• Incorporates message queues for asynchronous processing

• Each microservice is responsible for a specific domain or functionality

• Data is stored in a combination of relational and NoSQL databases

Find all triplets in an array of integers without duplicates

• Iterate through the array and for each element, find all pairs that sum up to the negative of that element

• Use a set to store the seen elements to avoid duplicates

• Time complexity can be improved to O(n^2) by sorting the array first

To find all square matrices in a given matrix, iterate through each cell as the top left corner of a potential square matrix and check if all elements within the square are the same.

• Iterate through each cell in the matrix as the top left corner of a potential square matrix

• For each cell, check if all elements within the square formed by the cell are the same

• If all elements are the same, consider it as a square matrix

Loop through the linked list to find and remove a specific node

• Start at the head of the linked list and iterate through each node

• Check if the current node matches the one to be removed

• If found, update the pointers to skip over the node and remove it

• Continue until the end of the list is reached

The question is asking to calculate the number of hops an elevator needs to travel between floors.

• Calculate the difference between the starting floor and the destination floor

• Divide the difference by the maximum number of floors the elevator can travel in one hop

• Round up the result to get the number of hops needed

Implementing hashmap in Java

• Create an array of linked lists to store key-value pairs

• Hash the key to get the index of the array

• Insert the key-value pair at the index in the linked list

• Handle collisions by chaining

• Implement methods like put(), get(), remove()

• Use generics to allow any type of key-value pairs

Transactions in Spring Boot manage database transactions in a declarative way.

• Spring Boot uses @Transactional annotation to mark a method as transactional.

• Transactions can be managed at class level or method level.

• Rollback can be configured based on specific exceptions.

• Example: @Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)