70+ Paras Spices Interview Questions and Answers

Algorithm to find if a number is present in a sorted n x n matrix with linear time complexity.

• Start with the top right element

• Compare the element with x

• If equal, return its position

• If e < x, move down (if out of bounds, return false)

• If e > x, move left (if out of bounds, return false)

• Repeat till element is found or returned false

The problem is to find non-empty subsets of a given set of integers whose sum is zero.

• The problem is a special case of the knapsack problem and is known to be NP-Complete.

• A brute-force approach would involve generating all subsets and checking their sums.

• The brute-force approach has an exponential time complexity.

• There is no known polynomial time solution for this problem.

Divide a rectangle of M x N into smaller rectangles of M1 x N1 to minimize wastage.

• Start by dividing the rectangle horizontally or vertically based on the dimensions of the smaller rectangles.

• Continue dividing each resulting sub-rectangle until no further division is possible.

• Consider the dimensions of the smaller rectangles and the remaining space to minimize wastage.

• Keep track of the divisions made to reconstruct the original rectangle if needed.

The glasses are stacked like a pyramid on a table. Each glass can hold a certain amount of water, and the overflow is distributed equally to the glasses below.

• The glasses form a pyramid shape, with the topmost glass being the first level and each subsequent level having one more glass than the previous level.

• The amount of water held by each glass can be calculated by dividing the total amount of water by the number of glasses in that level.

• For example, if there are 10 glasses...read more

Data structure with O(1) insert, delete, and find min without creating new structures

• Use two stacks, one for actual data and one for minimum values

• When inserting, push the value onto the data stack and push the minimum of the new value and the top of the minimum stack onto the minimum stack

• When deleting, pop from both stacks

• When finding the minimum, return the top of the minimum stack

Algorithm to list Fibonacci series and find median of combined array with and without 3rd array

• For Fibonacci series, start with 0 and 1, then add previous two numbers to get next number

• For finding median of combined array, merge the two arrays and sort them, then find the middle element(s)

• For finding median without 3rd array, use two pointers to traverse both arrays simultaneously and keep track of previous and current elements

A car sharing app that connects car owners with people who need a ride.

• Users can search for available cars in their area and book a ride.

• Car owners can list their car and set their own price for the ride.

• The app should have a rating system for both drivers and passengers.

• Payment should be handled through the app.

• Customer acquisition strategy can include social media advertising, referral programs, and partnerships with local businesses.

Factors to consider while designing a recommendation engine for a news website like MSN.

• Identify user preferences and behavior

• Analyze user history and engagement

• Consider content relevance and recency

• Incorporate social media trends and user feedback

• Use collaborative filtering and machine learning algorithms

• Ensure diversity in recommendations

• Optimize for speed and scalability

The number of 'BB' occurrences at the Nth iteration of the transformation sequence.

• At each iteration, A gets transformed to AB and B gets transformed to BA.

• To find the number of 'BB' occurrences at the Nth iteration, we need to count the number of 'BB' substrings in the transformed string.

• The transformation sequence follows a pattern: AB, ABA, ABAAB, ABAABABA, ...

• The number of 'BB' occurrences doubles with each iteration: 0, 0, 1, 2, 4, 8, 16, ...

• To calculate the number of 'B...read more

Sorting an array of 0, 1 and 2 can be done in O(n) using two pointers.

• Use two pointers, one for 0 and one for 2, and a current pointer to traverse the array

• If the current pointer encounters a 0, swap it with the 0 pointer and move both pointers to the right

• If the current pointer encounters a 2, swap it with the 2 pointer and move the 2 pointer to the left

• Repeat until the current pointer meets the 2 pointer

The bid for the AdWord should be based on the value of a click and the conversion rate.

• Calculate the value of a click by estimating the revenue generated per click.

• Determine the conversion rate of the website to estimate the number of clicks needed to generate a sale.

• Consider the competition for the keyword and adjust the bid accordingly.

• Use tools like Google Keyword Planner to estimate the bid range for the keyword.

• Regularly monitor and adjust the bid based on performance.

• Ex...read more

Ad fraud and detecting bot fraud mechanisms

• Ad fraud can be carried out through click fraud, impression fraud, and conversion fraud

• Detecting bot fraud can be done through analyzing user behavior, IP addresses, and device information

• Other mechanisms include using machine learning algorithms and third-party verification tools

• Examples of bot fraud detection tools include WhiteOps, DoubleVerify, and Integral Ad Science

Output all edges in any shortest path from x to y in an undirected weighted graph

• Use Dijkstra's algorithm to find all shortest paths from x to y

• Store the predecessor of each vertex to reconstruct the paths

• Output all edges in any of the shortest paths found

The case solution submitted suggested features such as personalized recommendations, social media integration, and a user-friendly interface.

• Personalized recommendations based on user behavior and preferences

• Social media integration for easy sharing and promotion

• User-friendly interface with intuitive navigation and clear calls to action

• Integration with third-party services such as payment gateways and shipping providers

• Robust analytics and reporting tools for tracking perform...read more

Given a string and pairs of indices, output the lexicographically smallest string after swapping characters.

• Sort the pairs based on the first index in ascending order.

• Use union-find data structure to keep track of connected components.

• Swap characters in the string based on the connected components.

• Return the lexicographically smallest string.

The subscription feature is a revenue stream.

• Subscription feature allows users to pay for premium content or services.

• Estimate revenue based on current user base and potential growth.

• Consider pricing strategy and competition.

• Example: Spotify Premium generates $1.5 billion in revenue annually.

Use binary search starting from top right corner to find the number in O(n+m) complexity.

• Start from the top right corner of the matrix

• If the current number is greater than the target, move left

• If the current number is less than the target, move down

• Repeat until the number is found or out of bounds

The value of x will depend on the execution order of the threads.

• The function fun() increments the value of x by 1.

• If all three threads run the function concurrently, the final value of x will be 8.

• If the threads run sequentially, the final value of x will be 7.

To find the country of an IP address from a CSV file, we can use a lookup table based on the IP address range.

• Create a lookup table from the CSV file with IP address ranges and corresponding country codes

• Parse the given IP address and match it with the ranges in the lookup table to find the corresponding country code

• Use binary search for efficient lookup in the IP address ranges

• Handle cases where the given IP address falls outside the ranges in the lookup table

Storing cookies on the client system allows for personalized user experiences and reduces server load.

• Storing cookies on the client system allows for faster access to user data without the need to constantly query the server.

• Cookies can store user preferences and login information, making the browsing experience more personalized.

• Server-side storage of cookies would require more server resources and could slow down the website's performance.

• Client-side storage also allows for...read more

Threads allow for more efficient use of resources and better performance compared to running concurrent processes.

• Threads are lighter weight than processes, requiring less overhead to create and manage.

• Threads share the same memory space, allowing for easier communication and data sharing between threads.

• Threads are more efficient for tasks that require frequent communication or synchronization.

• Threads are commonly used in GUI applications to keep the user interface responsiv...read more

No, we cannot implement overloading using different return types of function.

• Overloading is based on the number and types of parameters, not the return type.

• If we have two functions with the same name and parameters but different return types, it will result in a compilation error.

• Return type alone is not sufficient to differentiate between overloaded functions.

To detect a loop in a linked list, we can use Floyd's Cycle Detection Algorithm.

• Use two pointers, one moving at twice the speed of the other

• If there is a loop, the two pointers will eventually meet at some point

• Alternatively, use a hash set to store visited nodes and check for duplicates

Find a rectangular region in a binary matrix with k 1's.

• Iterate over all possible rectangular regions and count the number of 1's in each.

• Use a sliding window approach to efficiently count the number of 1's in each rectangular region.

• Use dynamic programming to precompute the number of 1's in each sub-rectangle and answer queries in constant time.

The angle between the hour hand and minute hand of a clock can be calculated using a simple formula.

• The angle between the hour hand and minute hand is given by the formula: |(30H - 11/2) - 6M| degrees

• H is the hour hand position and M is the minute hand position

• If the result is greater than 180 degrees, subtract it from 360 degrees to get the acute angle

Overriding is a concept in object-oriented programming where a subclass provides a specific implementation of a method that is already provided by its superclass.

• Overriding allows a subclass to provide a specific implementation of a method that is already defined in its superclass.

• It is used to achieve runtime polymorphism in object-oriented programming.

• The method in the subclass must have the same name, return type, and parameters as the method in the superclass to override ...read more

Find any duplicate number in an array of very big size

• Use a hash table to keep track of visited numbers

• Iterate through the array and check if the number is already in the hash table

• If it is, return the number as duplicate

Find indices i and j such that A[i]>a[j] and i>j such that ij is minimum

• Iterate through the array and keep track of the minimum value and its index

• Iterate through the array again and check if A[i]>min and i

• If yes, update the minimum index to j

• Return the minimum index

• Time complexity: O(n)

The virtual keyword is used in object-oriented programming to indicate that a method or property can be overridden in a derived class.

• The virtual keyword allows for polymorphism, where a derived class can provide its own implementation of a method or property inherited from a base class.

• It enables the concept of dynamic dispatch, where the appropriate method implementation is determined at runtime based on the actual type of the object.

• The virtual keyword is typically used in...read more

Sliding window protocol is a technique used in computer networks to ensure reliable and efficient data transmission.

• Sliding window protocol is used to manage the flow of data between sender and receiver in a network.

• It divides the data into small packets and assigns a sequence number to each packet.

• The sender sends a fixed number of packets and waits for acknowledgment from the receiver before sending more packets.

• If an acknowledgment is not received within a certain time, th...read more

Threads provide a lightweight way to achieve multitasking within a process.

• Threads share the same memory space, while processes have separate memory spaces.

• Threads are faster to create and terminate compared to processes.

• Threads allow for efficient communication and synchronization between different parts of a program.

• Threads are commonly used in applications that require concurrent execution, such as web servers or multimedia software.

• Example: In a web server, multiple threa...read more

Finding majority element in an array

• Use a hash table to store the frequency of each element

• Iterate through the hash table to find the element with frequency greater than n/2

• If no such element exists, return -1

Find the maximum sum of non-consecutive elements in an array.

• Create an array to store the maximum sum up to each index.

• Iterate through the array and calculate the maximum sum at each index.

• Return the maximum sum at the last index of the array.

• Exclude consecutive elements by skipping the previous index in the sum calculation.