SDE - 1

Operating Systems, DBMS and Computer Networks: This section had moderate-difficult level questions based on OS, DBMS, CN and troubleshooting. If you have a good grasp over the subjects then it wont be difficult to ace this round. 

You have been given a Binary Tree of integers. You are supposed to return the level order traversal of the given tree.

For example:

For the given binary tree

The level order traversal will be {1,2,3,4,5,6,7}.

You are given a string 'str' of length 'N'.

Your task is to reverse the original string word by word.

There can be multiple spaces between two words and there can be leading or trailing spaces but in the output reversed string you need to put a single space between two words, and your reversed string should not contain leading or trailing spaces.

Example :

If the given input string is "Welcome to Coding Ninjas", then you should return "Ninjas Coding to Welcome" as the reversed string has only a single space between two words and there is no leading or trailing space.

1) Suppose I have a brand new laptop and I wish to connect it to the internet. What should I do, and what shall happen in background before the laptop is connected to the internet? 

Ans. Manually assigning IP address or DHCP and DORA procedure. They expect you to explain in depth about DHCP and DORA

2) What happens in background when I write www.amazon.com on my web browser and hit enter? 

Ans. Complete process starting from how IP address request is sent from browser to OS to the DNS resolver and further, and how IP address is sent back to browser; after which the three-way-handshake procedure to establish TCP connection, and then how a request and response is generated followed by interpretation of HTML and Javascript along with images/sounds. 

1) What are few methods of HTTP, what is HTTPs, is the port number different for HTTPs, how is SSL related to HTTPs, explain SSL handshake?
2) How is a hub, a router, and a switch different from each other? Explain in terms of broadcast domain.
3) As MSS was explained in TCP 3 way handshake, explain what is MTU and compare and contrast MSS and MTU together.
4) Explain in depth what is TCP and UDP. Compare and contrast both of them.
5) What methods are available to us in flow control and error detection/correction?
6) What is public IP? How is it different from private IP? Can I connect to the internet using private IP? What is NAT?

Other important topics for AWS Networking Interview- Subnetting, OSI model with complete details and protocols on each layer, firewall in detail with all types (advantages/disadvantages)

Technical round: Asked general questions about networking, os and troubleshooting.

1.What are the advantages of having virtual memory?
2.How to trouble shoot windows system which has booting problems?
3.gave one simple code to implement and some general questions

1) What are different types of memory present in a computer?
2) Explain the concept of virtual memory. If it’s not present in hardware, how does it store data? Explain framing, segmentation and paging.
3) Explain the entire boot process of windows. (choice was given between Windows and Linux)
4) What is cache? What are its different types? Explain the entire process of searching in memory using hit and miss.
5) A memory shortage scenario was given and LRU algorithm was asked in a twisted form.

1) Troubleshooting: I am not able to connect to the internet. I do not have a spare device with me. Troubleshoot the scenario and figure out where does the issue lie? (Ans. Issue can lie with the device, or the network, or from the server side. This needs to be answered strategically from the most common issue raised first, to the least common possibility addressed last)

2) Troubleshooting: My device is heating up very quickly. Troubleshoot the scenario.
 

3) Troubleshooting: I am trying to transfer media over FTP from one device to another. The rate of transfer is very slow. Troubleshoot the scenario.

4) Brief questions related to my major project (7th semester) and related technology were asked towards the end of the interview.

How you’ve handled conflict with coworkers.

How you’ve handled high-pressure situations.

What are the 14 leadership principles of Amazon.