10+ Pratiti Technologies Interview Questions and Answers

Find the first k most occurring strings from a given list

• Use a hashmap to store the frequency of each string

• Sort the hashmap based on frequency in descending order

• Return the first k keys from the sorted hashmap

Design a database schema for a train booking system

• Create tables for trains, stations, bookings, users, and tickets

• Use foreign keys to establish relationships between tables

• Include columns for train schedule, seat availability, and user information

• Consider implementing indexes for faster query performance

Binary search algorithm can be used to find a target element in a sorted array.

• Implement binary search algorithm to efficiently find the target element in a sorted array.

• Compare the target element with the middle element of the array and adjust the search range accordingly.

• Continue dividing the search range in half until the target element is found or the search range is empty.

React hooks are functions that let you use state and other React features without writing a class.

• React hooks were introduced in React 16.8 to allow functional components to have state and lifecycle methods.

• useState() is a hook that allows you to add state to functional components.

• useEffect() is a hook that allows you to perform side effects in functional components.

• Custom hooks are reusable functions that can contain logic and state.

• Hooks should always be used at the top lev...read more

Use Depth First Search (DFS) to detect cycle in a graph. Remove an edge from the cycle to make it acyclic.

• Implement Depth First Search (DFS) to detect cycles in the graph

• If a back edge is found during DFS traversal, it indicates a cycle in the graph

• Remove an edge from the cycle to make the graph acyclic

Find maximum sum of distinct subarray with length k using sliding window technique.

• Use a sliding window of size k to iterate through the array

• Keep track of the sum of elements within the window

• Maintain a set to keep track of distinct elements in the window

• Slide the window by removing the leftmost element and adding the rightmost element

• Update the maximum sum as you iterate through the array

Browser rendering process involves multiple steps from parsing HTML to displaying content on the screen.

• HTML parsing: Browser parses HTML markup to create the Document Object Model (DOM).

• CSS parsing: Stylesheets are parsed to create the CSS Object Model (CSSOM).

• Render tree construction: DOM and CSSOM are combined to create the render tree.

• Layout: The render tree is laid out to determine the position and size of each element.

• Painting: Finally, the browser paints pixels on the ...read more

Sort an array of strings containing only '0', '1', and '2'.

• Use a counting sort algorithm to count the occurrences of '0', '1', and '2'.

• Create a new array based on the counts of each element.

• Alternatively, use the Dutch National Flag algorithm to sort the array in-place.

Find the next greater element in an array

• Iterate through the array and use a stack to keep track of elements

• For each element, pop elements from the stack until finding a greater element

• Store the next greater element in a result array