40+ Infosys Interview Questions and Answers

I have used platforms such as Excel, Tableau, and Power BI for data analysis in the past.

• Excel

• Tableau

• Power BI

Trade life cycle refers to the stages involved in a trade from initiation to settlement.

• Trade initiation - Trade is proposed and agreed upon by parties involved

• Trade execution - Trade is executed on the exchange or over-the-counter market

• Trade confirmation - Parties confirm the details of the trade

• Trade settlement - Payment and transfer of securities occur

• Trade reconciliation - Ensuring all details match between parties

To improve model performance beyond hyperopt, consider ensemble methods, feature engineering, and data augmentation.

• Implement ensemble methods like bagging, boosting, or stacking to combine multiple models.

• Perform feature engineering to create new informative features or transform existing ones.

• Apply data augmentation techniques to increase the size and diversity of the training data.

• Consider using advanced algorithms like XGBoost, Random Forest, or Neural Networks.

• Regularize...read more

To tune model performance, adjust hyperparameters, preprocess data, increase training data, and use ensemble methods.

• Adjust hyperparameters such as learning rate, regularization, and batch size.

• Preprocess data by scaling, normalizing, or handling missing values.

• Increase training data to reduce overfitting and improve generalization.

• Use ensemble methods like bagging or boosting to combine multiple models.

• Perform cross-validation to evaluate model performance and select the bes...read more

Handling class imbalance involves techniques such as resampling, adjusting class weights, and using ensemble methods.

• Resampling techniques like oversampling the minority class or undersampling the majority class can help balance the classes.

• Adjusting class weights during model training can give more importance to the minority class.

• Using ensemble methods like bagging or boosting can improve the performance on imbalanced datasets.

• Applying anomaly detection or one-class classif...read more

KYC refers to the process of verifying the identity of customers and assessing their potential risks.

• KYC stands for Know Your Customer

• KYC documents include identity proof, address proof, and other relevant documents

• In my previous organization, I learned about the importance of verifying customer identities to prevent fraud and financial crimes

• I have implemented process improvements to streamline the KYC process and reduce turnaround time

• The outcomes of these solutions were im...read more

XGBoost is an optimized version of Gradient Boosting Machine (GBM) with additional features and improvements.

• XGBoost is a scalable and efficient implementation of gradient boosting algorithm.

• XGBoost uses a more regularized model formalization to control overfitting.

• XGBoost supports parallel processing and can handle large datasets.

• XGBoost provides built-in regularization techniques like L1 and L2 regularization.

• XGBoost has a variety of objective functions and evaluation metri...read more

The gas and track problem involves determining the amount of gas required to complete a track.

• Calculate the distance of the track

• Determine the fuel efficiency of the vehicle

• Divide the distance by the fuel efficiency to get the required amount of gas

Create a Binary Search Tree (BST) from an incoming stream of nodes.

• Start with an empty BST

• For each incoming node, compare it with the root node and insert it accordingly

• Repeat the process until all nodes are inserted

Find the next largest in the right side for every array element.

• Iterate through the array from right to left

• Use a stack to keep track of elements

• Pop elements from stack until a greater element is found

• If no greater element is found, assign -1

Yes, we have implemented automation in our customer service department.

• We have implemented chatbots to handle basic customer queries.

• We have also automated the process of ticket creation and assignment.

• This has resulted in faster resolution times and increased customer satisfaction.

• We have also used data analytics to identify common customer issues and proactively address them.

• This has reduced the number of customer complaints and improved overall efficiency.

Designing a food delivery app

• Identify target audience and their needs

• Create user-friendly interface for ordering food

• Integrate payment gateway for easy transactions

• Develop a tracking system for delivery status

• Ensure timely delivery and quality of food

• Implement customer feedback system for improvement

• Partner with local restaurants for wider menu options

Disputes, banking, complaints, and SLA are key aspects of customer service in the financial industry.

• Disputes in banking refer to disagreements between customers and financial institutions regarding transactions or services.

• Complaints are formal expressions of dissatisfaction from customers about the services provided by a bank.

• SLA (Service Level Agreement) is a contract between a service provider and a customer that outlines the level of service expected.

• Effective handling o...read more

AML and KYC requirements are regulations that financial institutions must follow to prevent money laundering and verify the identity of their customers.

• AML (Anti-Money Laundering) requirements involve monitoring transactions, reporting suspicious activities, and conducting customer due diligence.

• KYC (Know Your Customer) requirements involve verifying the identity of customers, assessing their risk level, and maintaining updated customer information.

• Examples of AML and KYC req...read more

Find shortest path in 0,1 matrix from (0,0) to (n-1,n-1)

• Use Breadth First Search (BFS) algorithm to find shortest path

• Create a visited matrix to keep track of visited nodes

• Create a distance matrix to keep track of distance from source node

• Start BFS from (0,0) and keep updating visited and distance matrices

• Return distance value at (n-1,n-1) in distance matrix

Java 8 introduced lambda expressions, functional interfaces, and forEach method.

• Lambda expressions allow functional programming in Java.

• Functional interfaces are interfaces with only one abstract method.

• forEach method is used to iterate over collections in a concise way.

• Stream API is also introduced in Java 8 for processing collections.

• Optional class is introduced to handle null values.

• Default and static methods are also introduced in interfaces.

Trapping rainwater problem

• The problem involves calculating the amount of rainwater that can be trapped between bars in an elevation map

• Use two pointers approach to calculate the water trapped at each bar

• Keep track of the maximum height on the left and right of each bar to calculate the trapped water

Search for a target value in a sorted n*n matrix.

• Start from the top-right corner or bottom-left corner of the matrix.

• Compare the target value with the current element and move left or down accordingly.

• Repeat until the target value is found or the boundaries of the matrix are crossed.

Find peak in array in less than O(n) time

• Use binary search to find peak element

• Compare middle element with its neighbors to determine direction

• Repeat search in direction of larger neighbor until peak is found

RCA stands for Root Cause Analysis and includes identifying the underlying cause of a problem or issue.

• Identifying the problem or issue

• Gathering data and evidence

• Analyzing the data to determine the root cause

• Developing and implementing solutions to address the root cause

• Monitoring and evaluating the effectiveness of the solutions

• Examples: RCA for a manufacturing defect, RCA for a customer complaint, RCA for a workplace accident

Chargeback and fraud are common issues in financial transactions, involving unauthorized transactions and disputes.

• Chargeback is a process where a customer disputes a transaction and the funds are returned to the customer.

• Fraud involves unauthorized or deceptive activities to gain financial advantage.

• Fraud can occur through various methods such as identity theft, phishing, and card skimming.

• Fraud analysts use data analysis and investigation techniques to detect and prevent fr...read more

Types of keys in SQL include primary, foreign, and unique. Types of joins include inner, outer, left, and right.

• Primary key: uniquely identifies each record in a table

• Foreign key: links two tables together

• Unique key: ensures that each value in a column is unique

• Inner join: returns only the matching rows from both tables

• Outer join: returns all rows from both tables, with null values for non-matching rows

• Left join: returns all rows from the left table and matching rows from the...read more

Chargebacks are a reversal of a credit card transaction by the card issuer.

• Chargebacks occur when a customer disputes a charge on their credit card statement.

• The card issuer investigates the dispute and may reverse the transaction if they find it to be valid.

• Merchants may be charged a fee for each chargeback they receive.

• Common reasons for chargebacks include fraud, product not received, or product not as described.

• Merchants can dispute chargebacks by providing evidence to th...read more

Finding the shortest super common string among an array of strings.

• Create a set of all substrings of the first string

• Iterate through the remaining strings and remove substrings not present in them

• Return the shortest remaining substring

Implement two stacks in a single array using two different approaches

• Divide the array into two halves and use one half for each stack

• Use two pointers, one for each stack, and move them towards each other as elements are pushed or popped

• Consider edge cases like stack overflow and underflow

SQL is a traditional relational database management system, while NoSQL is a non-relational database system.

• SQL is structured, uses tables with predefined schema, and is good for complex queries.

• NoSQL is unstructured, uses collections or documents, and is good for large amounts of data with simple queries.

• SQL is ACID compliant, ensuring data integrity, while NoSQL is BASE (Basically Available, Soft state, Eventually consistent) for scalability and flexibility.

• Examples of SQL ...read more

Reverse a linked list recursively by swapping pointers

• Start by checking if the current node is null or the next node is null

• If so, return the current node as it is the new head of the reversed list

• Otherwise, recursively call the function on the next node and swap pointers

A system like Zomato for restaurant discovery and food ordering.

• Create a database of restaurants with details like menu, location, ratings, etc.

• Develop a user-friendly website and mobile app for easy access.

• Implement a search feature for finding restaurants based on location, cuisine, etc.

• Allow users to rate and review restaurants.

• Integrate a secure payment gateway for online food ordering and delivery.

• Partner with restaurants for promotions and discounts.

• Provide analytics an...read more

To find a number in a sorted rotated array, use binary search algorithm.

• Identify the mid element of the array

• Check if the mid element is the target number

• If not, check if the left half or right half of the array is sorted

• If the left half is sorted and the target number falls within that range, search in the left half

• If the right half is sorted and the target number falls within that range, search in the right half

• Repeat the process until the target number is found or the arra...read more

A min stack is a stack data structure that supports the usual push and pop operations, along with an additional operation to retrieve the minimum element in constant time.

• Create a stack to store the elements and another stack to store the minimum values encountered so far.

• When pushing an element, check if it is smaller than the current minimum. If so, push it onto the minimum stack.

• When popping an element, check if it is equal to the current minimum. If so, pop from the minim...read more

Design the Low Level Design (LLD) for a Parking Lot System

• Divide the system into modules like parking lot, vehicle, ticket, payment, etc.

• Define the classes and their relationships, such as ParkingLot, Vehicle, Ticket, Payment

• Include methods for functionalities like parking a vehicle, issuing a ticket, processing payment

• Consider scalability and performance aspects in the design

• Implement data structures like queues for managing parking spots

Designing a notification system for efficient communication and updates.

• Identify the target audience for the notifications (employees, customers, etc.)

• Determine the types of notifications needed (urgent alerts, general updates, reminders, etc.)

• Choose the appropriate communication channels (email, SMS, app notifications, etc.)

• Implement a user-friendly interface for managing notification preferences

• Include options for customization and personalization of notifications

Design a parking system for efficient and organized parking.

• Consider different types of parking spaces (e.g. regular, compact, handicap)

• Implement a ticketing system for tracking parked cars

• Incorporate sensors for real-time monitoring of available spaces

• Include a payment system for paid parking spots

• Design a user-friendly interface for drivers to easily find parking spots

Inner join combines rows from two tables based on a related column

• Inner join returns only the rows that have matching values in both tables

• It is used to retrieve data that exists in both tables

• Example: SELECT Orders.OrderID, Customers.CustomerName FROM Orders INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;

HashMap is a data structure that stores key-value pairs and uses hashing to quickly retrieve values based on keys.

• HashMap internally uses an array of linked lists to store key-value pairs.

• When a key-value pair is added, the key is hashed to determine the index in the array where the pair will be stored.

• If multiple keys hash to the same index, a linked list is used to handle collisions.

• HashMap allows null keys and values, but only one null key.

• Example: HashMap map = new HashMa...read more

My current process involves analyzing data, identifying trends, and creating reports to support decision-making.

• Collecting relevant data from various sources

• Using statistical tools and software to analyze data

• Creating visualizations and reports to communicate findings

• Presenting findings to stakeholders for decision-making

Designing a file system involves organizing and managing data on a storage device.

• Consider the type of data to be stored and access patterns

• Choose a suitable file system structure (e.g. FAT, NTFS, ext4)

• Implement features like file permissions, encryption, and compression

• Plan for scalability and backup strategies