Design-UX-CSS and Question on MongoDB

Round 1 (Technical F2F):

The interviewer started by asking about my current project and asked me to explain the architecture. I answered by explaining her the complete architecture on the white board. Then she asked how much would I rate myself in DS & Algo on a scale of 1-10. Then she asked the following questions:

1. Reverse a linked list.
2. Cloning a linked list having next and random pointer. 3)Mirror of a Binary tree.

Questions on Java:

1)Difference between static synchronized block and non static Synchronized block. 2)Why wait() , notify() and notifyAll() methods are in Object class. 3)Why string is Immutable? Is it possible to have a synchronized block that locks on to a String object?

Question on MongoDB:

1)How to achieve Horizontal scaling in MongoDB.What all servers are required to do the same.

2)There’s a student collection which has multiple documents for different subjects.How to aggregate all records of all students and have a single array field having all marks of a given student.

Round 2 (Technical F2F): This round was the toughest, not because the questions were tough but it lasted forever(more than 3 hours)

1) Problem statement:

There’s a file that contains URL and description of some websites delimited by comma.I need to read that file and write it back to another file in a sorted manner. The input file may have different description for same website.Ex: www.google.com/blogs/career , www.google.com/ home/etc will have different descriptions. The output file should have only one entry for a particular website but can have many descriptions. I gave him a solution which he felt was good. He then altered the problem statement . Now, instead of 1 file there is a directory of files and all needs to be read and written back in a new file in sorted manner.He hinted that he’s looking for a multi threaded solution . I gave a solution using Thread pool executor and after a long discussion he was happy with the solution.

2. What is Hash code? Difference between HashMap and HashTable ? How HashMap is implemented internally? How linear probing leads to clustering? Can we have null key in a HashMap?

3. He asked me to explain Observer pattern (because I had told him that I used it in one of the projects ) . He asked me to move over to the white board and explain with proper class diagrams. Why composition is preferred over inheritance was one of the many questions that he asked while I was explaining implementation of observer pattern.

4)What are deadlocks ? When do they occur? How to avoid them? How to avoid them in Java?Write a code that leads to a deadlock.

5)There’s a website that shows online content when there’s internet connection and offline content like downloads when offline.There’s a switch that tells if the website is online or offline.There’s a display() method that displays the appropriate content.How to implement that display method?He was not really looking for any code but the approach . I told him that we’ll have a Screen interface that has a display() method and there would be two concrete implementations : online screen and offline screen of the screen interface where I’ll override the display() method. He was content with solution.

6. Implement a BST which supports insertion , deletion and search.

7. Rotate an array by K times.

8. Given an array find the maximum value of Σarr[i]*i, where i = 0, 1, 2,…., n – 1.( https://www.geeksforgeeks.org/maximize-sum-arrii/)

9. Why to prefer Synchronized block over Synchronized method?

10. Explain Quick sort .

Round 3 (Technical F2F):

1. When should we go for in memory caching? (because my resume says that I’ve worked on MemcacheD)
2. Explain micro services architecture.(I explained him with an overview of how docker containers work and how we can have container orchestration using Kuberenetes)
3. How Agile way of development is different from the traditional waterfall model?
4. How PAAS is different from IAAS.(Cloud computing)
5. Implement a queue using stack.

Round 4(Managerial + Technical F2F)

1)How to kick start a springboot application? 2)What are the different scope of Spring beans? 3) Difference between PUT and PATCH requests in REST api. 4)Why do you want to join SAP labs?

Round 5 (Technical -Telephonic): This was a cross LOB round where a person from a different team interviewed. 1)How to achieve Many2Many mappings in Hibernate. 2)Use of @Qulifier annotation in Spring? 3) How dispatcher servlet works? 4)How a class in loaded into JVM?

Round 6( HR) The basic HR questions : Where do you see yourself in 5 years? Why do you want to quit your cureent job? Salary negotiation .(Which I regret not doing.)

Finally got the offer !!

• Talk about the pros and cons of flat and skeuomorphic design trends in regards to accessibility.
• Explain the importance of color contrast in designing for inclusion.
• Besides :hover, name other states an actionable element (links, buttons, form controls, etc.) could have styles for, and why providing them is important?
• When might it be appropriate to remove the visual outline from a focused element?
• If a form or form field were to return an error message, where might you want those error messages to be located?
• How can utilizing animation in an interface affect the user experience?
• Explain how you could make an infographic accessible for screen reader users.
• Why is color alone insufficient to draw attention to actionable elements, or to convey state?
• What are some of the inclusive UX problems that need to be solved when content (static or actionable) is revealed on :hover, and how would you propose solving for them?

Network-questions

• Traditionally, why has it been better to serve site assets from multiple domains?
• Do your best to describe the process from the time you type in a website’s URL to it finishing loading on your screen.
• What are the differences between Long-Polling, Websockets and Server-Sent Events?
• Explain the following request and response headers:
  • Diff. between Expires, Date, Age and If-Modified-…
  • Do Not Track
  • Cache-Control
  • Transfer-Encoding
  • ETag
  • X-Frame-Options
• What are HTTP methods? List all HTTP methods that you know, and explain them.
• What is domain pre-fetching and how does it help with performance?
• What is a CDN and what is the benefit of using one?

• What tools would you use to find a performance bug in your code?
• What are some ways you may improve your website’s scrolling performance?
• Explain the difference between layout, painting and compositing.
• When building a new web site or maintaining one, can you explain some techniques you have used to increase performance?
• Can you describe some SEO best practices or techniques you have used lately?
• Can you explain any common techniques or recent issues solved in regards to front-end security?
• How many resources will a browser download from a given domain at a time?
• What does CORS stand for and what issue does it address?

 

The interviewer started by asking about my current project and asked me to explain the architecture. I answered by explaining her the complete architecture on the white board. Then she asked how much would I rate myself in DS & Algo on a scale of 1-10. Then she asked the following questions:

1. Reverse a linked list.
2. Cloning a linked list having next and random pointer. 3)Mirror of a Binary tree.

Questions on Java:

1)Difference between static synchronized block and non static Synchronized block. 2)Why wait() , notify() and notifyAll() methods are in Object class. 3)Why string is Immutable? Is it possible to have a synchronized block that locks on to a String object?

Question on MongoDB:

1)How to achieve Horizontal scaling in MongoDB.What all servers are required to do the same.

2)There’s a student collection which has multiple documents for different subjects.How to aggregate all records of all students and have a single array field having all marks of a given student.

Round 2 (Technical F2F): This round was the toughest, not because the questions were tough but it lasted forever(more than 3 hours)

1) Problem statement:

There’s a file that contains URL and description of some websites delimited by comma.I need to read that file and write it back to another file in a sorted manner. The input file may have different description for same website.Ex: www.google.com/blogs/career , www.google.com/ home/etc will have different descriptions. The output file should have only one entry for a particular website but can have many descriptions. I gave him a solution which he felt was good. He then altered the problem statement . Now, instead of 1 file there is a directory of files and all needs to be read and written back in a new file in sorted manner.He hinted that he’s looking for a multi threaded solution . I gave a solution using Thread pool executor and after a long discussion he was happy with the solution.

2. What is Hash code? Difference between HashMap and HashTable ? How HashMap is implemented internally? How linear probing leads to clustering? Can we have null key in a HashMap?

3. He asked me to explain Observer pattern (because I had told him that I used it in one of the projects ) . He asked me to move over to the white board and explain with proper class diagrams. Why composition is preferred over inheritance was one of the many questions that he asked while I was explaining implementation of observer pattern.

4)What are deadlocks ? When do they occur? How to avoid them? How to avoid them in Java?Write a code that leads to a deadlock.

5)There’s a website that shows online content when there’s internet connection and offline content like downloads when offline.There’s a switch that tells if the website is online or offline.There’s a display() method that displays the appropriate content.How to implement that display method?He was not really looking for any code but the approach . I told him that we’ll have a Screen interface that has a display() method and there would be two concrete implementations : online screen and offline screen of the screen interface where I’ll override the display() method. He was content with solution.

6. Implement a BST which supports insertion , deletion and search.

7. Rotate an array by K times.

8. Given an array find the maximum value of Σarr[i]*i, where i = 0, 1, 2,…., n – 1.( https://www.geeksforgeeks.org/maximize-sum-arrii/)

9. Why to prefer Synchronized block over Synchronized method?

10. Explain Quick sort .

Round 3 (Technical F2F):

1. When should we go for in memory caching? (because my resume says that I’ve worked on MemcacheD)
2. Explain micro services architecture.(I explained him with an overview of how docker containers work and how we can have container orchestration using Kuberenetes)
3. How Agile way of development is different from the traditional waterfall model?
4. How PAAS is different from IAAS.(Cloud computing)
5. Implement a queue using stack.

Round 4(Managerial + Technical F2F)

1)How to kick start a springboot application? 2)What are the different scope of Spring beans? 3) Difference between PUT and PATCH requests in REST api. 4)Why do you want to join SAP labs?

Round 5 (Technical -Telephonic): This was a cross LOB round where a person from a different team interviewed. 1)How to achieve Many2Many mappings in Hibernate. 2)Use of @Qulifier annotation in Spring? 3) How dispatcher servlet works? 4)How a class in loaded into JVM?

Round 6( HR) The basic HR questions : Where do you see yourself in 5 years? Why do you want to quit your cureent job? Salary negotiation .(Which I regret not doing.)

Organizational Systems and Team Process Questions for Mid-to-Senior Lavel

• What is your workflow currently, with regards to developers pushing changes.
  • Do you do pull requests, or does everyone just merge to a central repo?
  • What branching method do you use? (Git-Flow, Github-Flow, Environment Merging, something custom)

• Are you using a ticket system or is it more play it by ear?
  • Do you use the same system for both bugs and new features?
  • How is priority determined?
  • What comes first, bugs or features?
  • Are detailed requirements for tasks determined and documented ahead of time?
  • How are tasks added to the backlog?

• Who determines the features that would go into the product? How are these chosen?

  • How are developers involved in that decision?
  • How are testers involved in that process?

• How do you track development time?

• Do you have a code review process?

  • Does your code review process prevent deploying code?
  • Does your code review process promote empathy?

• Does your team encourage the use of SOLID and DRY design principles to avoid cyclomatic complexity?

• Do you have established code style rules?
  • Did you create your own style guide, or are you using a third party’s (PEP8, PSRs, Standard JS, etc)
  • Is there an automated linting process to validate your styles?
  • Tabs or spaces? (If relevant)
  • Allman or BSD braces? (If relevant)
  • Semicolons? (If relevant)

• How is QA/testing done?

  • Are developers expected to do testing as well? To what extent?
  • If there is a separate testing team, how is the co-ordination done between testing and development?
  • How is the decision made that a release is ready?

• Who designs the User Interface?

  • Are developers expected to do it?
  • Are there graphics designers in the company?
  • Are there UX designers in the company?

• Are there compliance requirements in the company like CMM or SOC?

• Do you have an SLA (Service Level Agreement)?

  • Do you guarantee any of the following? If so, how long?
    • Turn Around Time (TAT)?
    • Average Speed to Answer (ASA)
    • Time Service Factor (TSF)
  • What is the escalation plan? What are the consequences if the plan is not followed?

• Do you have an automated test suite?

  • What libraries and tools do you use?
  • What sorts of tests do you use? (unit, integration, system, load, …)
  • What is your testing methodology? (BDD, TDD, Spike & Stabilize, …)
  • What is your current level of test coverage? Are you happy with it?

• Do you regularly correct technical debt?

• On a scale of 1 to 10, how much spaghetti code do you have?

• How well-documented is your codebase?

  • Do you use automated documentation systems like PHPDoc or JSDoc?
  • Do you maintain a wiki?

Interview questions on React-Redux that I am yet to make a good note / ans of

1> How to optimize React component to render it less often? (using shouldComponentUpdate to determine if any relevant data changed)

2> What are best practices? (for example why not to use getInitialState, try to find others and know how to explain them)

3> React is rarely used by itself, so expect some questions about data layer, most commonly an implementation of flux:

4> What is flux? How it’s different from the more traditional MVC pattern?

5> How does Redux data flow work? (view, action creator, reducer, view — you should know and explain responsibilities of each; also how state is represented — state tree)

6> Comparison with Angular Js and VUE js?

7> Understanding on state, props, event handling, data sharing, ajax in react, polling, routing

8> Unit testing for React code

9> explain what is higher order component, control uncontrolled component in react.

10> Reducer return a new object or old one?

11> Explain diff between store and flux.

12> What is the difference between Virtual DOM and DOM?

13> Describe synthetic events in React. How it is different from Javascript Events.

14> Explain this.props.children

15> Differentiate controlled and uncontrolled components in React Js?

16> How to optimize React component to render it less often? (using shouldComponentUpdate to determine if any relevant data changed)

Amazon Behavioral questions | Leadership Principles | LP

1.https://interviewgenie.com/blog-1/category/Amazon+interviews

2.https://www.youtube.com/channel/UCw0uQHve23oMWgQcTTpgQsQ/playlists

3.https://medium.com/@scarletinked/are-you-the-leader-were-looking-for-interviewing-at-amazon-8301d787815d

• Tell me about a situation where you had a conflict with someone on your team. What was it about? What did you do? How did they react? What was the outcome?

• Give an example of when you saw a peer struggling and decided to step in and help. What was the situation and what actions did you take? What was the outcome?

• Tell me about a time you committed a mistake?

• Tell me about a time when your earned your teammate’s trust?

• Tell me about a time when you couldn’t meet your deadline?

• Tell me about a time when your teammate didn’t agree with you? What did you do?

• Tell me about a time when you invented something?

• Tell me about a time when you took important decision without any data?

• Tell me about a time when you helped one of your teammates?

• Have you ever been in a situation where you had to make a choice among a few options, but did not have a lot of time to explore each option

• Have you ever failed at something? What did you learn from it?

• name time when you went out of your way to help someone?

• Time when you came up with novel solution.

• Received negative feedback from manager and how you responded.

• Time when you went above and beyond your job responsibilities.

• Time when you did not have enough data and had to use judgement to make decision.

• Time when you helped someone in their work.

• Time when you helped someone grow in career and it benefited them.

• Time when you helped someone grow but did not benefit them.

• Time when you were 75% through a project and realized you had the wrong goal.

• Time when your team members were not supporting something but you pushed and went for a more optimal solution.

• Time when you pushed back a decision from your management for better long term benefits.

• Time when you failed to meet your commitment

• Tell me about yourself. Tell me about a project you’re working on.

• Time when you were working on a project on a time constraint

• Time when you didn’t meet a deadline

• Time when you needed help from somebody

• Tell me about yourself.

• Tell me about a time you had to help a team member struggling with a task.

• Tell me about a time you faced an obstacle and how you overcame it.

• Tell me about one of your projects?

• Tell me about one of your projects so the same as the first guy.

• Tell me a time you took some on some risk

• Have you ever gone out of your way to help a peer? (ownership)

• Have you ever had to make a tough decision without consulting anybody? (bias for action)

• asked me about my past projects that I’ve worked on and gave me detailed explaination about the Internship.

• Tell me about a time when you learned new technologies

• Tell me about a time when you took a decision on your own without the manager’s prior approval

• Tell me about a time you had multiple solutions and you had to select an optimal one

• Tell me about a time when you innovated and exceeded the expectation

• Tell me about a time where you had to make a decision based on limited information and how it impacted the outcome.

• Tell me about a time where you had limited time and how it impacted

• Tell me about a time where you did not know something and how you tackled it(Something related to it)

• first one was about handling a tight deadline, second is setbacks on projects?

• Handling a tight deadline

• How would you help a new employee who is facing technical difficulties?

• disagree and commit and ownership LPs.

• Tell me about your yourself (the general icebreaker).

• Tell me about tim when you faced a difficult challenge.

• Tell me about a time when you needed help from someone during a project.

• Tell me about a time when you thought of an unpopular idea.

• Tell me about a time when you had to decide upon something without consulting your superior.

• Tell me about a time when you had to face tight time constraints during a project.

• Tell me about yourself.

• Tell me about a time when you did not meet your deadlines for a project.

• Tell me about a time when you had conflicting ideas with your teammates and how did you resolve them?

• a project you’re proud of

• a time when you faced a setback initially but still achieved the goal.

• a time when you had to cut corners to meet a deadline

• “Tell me about a time when you felt under pressure that you wouldn’t be able to get something done or had to take a pivot at the last minute”