10+ Gack Billing Services Interview Questions and Answers

Consider web accessibility guidelines for disabled persons when writing HTML code.

• Use semantic HTML elements like <nav>, <header>, <main>, <footer> to improve screen reader accessibility.

• Provide alternative text for images using the alt attribute.

• Ensure proper color contrast for text and background to aid visually impaired users.

• Use ARIA roles and attributes to enhance accessibility for interactive elements.

• Test your website using screen readers and keyboard navigation to ide...read more

WebDriver supports two types of waits: implicit and explicit.

• Implicit wait: waits for a certain amount of time before throwing a NoSuchElementException if the element is not found

• Explicit wait: waits for a certain condition to occur before proceeding to the next step

• Examples of conditions for explicit wait: element to be clickable, element to be visible, element to have a certain text

• WebDriverWait class is used for explicit wait

Program in javascript to display a pyramid

• Use nested loops to print the pyramid

• The outer loop controls the number of rows

• The inner loop controls the number of spaces and asterisks to print

• Use string concatenation to build the pyramid

Program to sort an array

• Choose a sorting algorithm based on the requirements

• Implement the chosen algorithm in the programming language of choice

• Test the program with different input sizes and edge cases

BMC stands for Block Formatting Context in CSS, which is a mechanism for controlling the layout of elements.

• BMC is created when an element is floated, positioned absolutely, or has an overflow value other than visible.

• BMC prevents margin collapsing between parent and child elements.

• BMC can be used to create columns of equal height.

• Example: Using display: inline-block on child elements creates a BMC.

• Example: Using overflow: hidden on a parent element creates a BMC.

A COBOL program to print Fibonacci series using recursion.

• Use recursive function to calculate Fibonacci numbers

• Initialize variables for storing previous two Fibonacci numbers

• Print the Fibonacci series as it is calculated

CSS pre-processors are tools that extend the functionality of CSS by adding features like variables, nesting, and mixins.

• CSS pre-processors like Sass, Less, and Stylus allow for more efficient and organized CSS coding

• They offer features like variables, nesting, and mixins that make CSS code more modular and reusable

• Pre-processors need to be compiled into regular CSS before being used in a website

• They can be integrated into build tools like Grunt or Gulp for automated compilat...read more

Count the frequency of characters in a given string.

• Iterate through the string and count occurrences of each character.

• Use a dictionary to store character frequencies.

• Return the dictionary with character frequencies.

Counters in CSS can be created using the counter-reset and counter-increment properties.

• Use the counter-reset property to set the initial value of the counter

• Use the counter-increment property to increment the counter

• Use the content property to display the counter value

• Example: counter-reset: section; counter-increment: section; content: counter(section);

Concurrency in JS allows multiple tasks to run simultaneously by utilizing event loop and callback functions.

• JS is single-threaded, meaning it can only execute one task at a time.

• Concurrency is achieved through asynchronous operations using callbacks, promises, and async/await.

• Event loop manages the execution of multiple tasks by queuing them in a stack and executing them one by one.

• Web Workers allow running scripts in background threads to handle heavy computations without b...read more

A dead loop queue is a situation where a process or thread is stuck in a loop without making progress.

• Occurs when a process or thread gets stuck in an infinite loop

• Can lead to system hang or crash if not handled properly

• Common in multi-threaded programming

I have experience in modernizing mainframe systems by migrating to cloud-based solutions and implementing modern technologies.

• Led a team in migrating legacy mainframe applications to cloud platforms such as AWS or Azure

• Implemented modernization strategies such as refactoring code, containerization, and microservices architecture

• Utilized tools like Docker, Kubernetes, and Jenkins to streamline the modernization process

Site reliability principles ensure systems are reliable, scalable, and efficient.

• Implementing automation for routine tasks to reduce human error

• Monitoring system performance and alerting for potential issues

• Designing systems with redundancy to prevent single points of failure

• Using load balancing to distribute traffic evenly across servers

• Performing regular capacity planning to ensure resources meet demand

Microservices design pattern focuses on breaking down applications into smaller, independent services.

• Microservices architecture involves breaking down a large application into smaller, independent services that communicate with each other through APIs.

• Each microservice is responsible for a specific function or feature of the application.

• Microservices allow for greater flexibility, scalability, and resilience in software development.

• Examples of companies using microservices i...read more

Selenium architecture is a framework that consists of different components for automated testing of web applications.

• Selenium WebDriver: Used for interacting with web elements and executing test scripts.

• Selenium Grid: Allows for parallel execution of tests across different browsers and operating systems.

• Selenium IDE: A record and playback tool for creating test scripts.

• Selenium RC (Remote Control): Deprecated component that used to be the predecessor of WebDriver.

• Selenium Ser...read more

Jenkins pipeline is a suite of plugins that supports implementing and integrating continuous delivery pipelines.

• Jenkins pipeline allows defining the entire build process as code, stored in a Jenkinsfile.

• It enables automation of the build, test, and deployment process, providing visibility and traceability.

• Pipeline stages can be defined to execute specific tasks like compiling code, running tests, and deploying artifacts.

• Declarative and scripted syntax are supported for defini...read more

The base location for joining will be discussed during the interview process.

• Base location will be determined based on company needs and candidate's preferences

• Candidates may have the option to choose from multiple locations

• Some companies offer remote work options