Today on 19 Sep I had my Infosys On Campus Interview, I was shortlisted for L3 role(specified in excel by TPC before interview). I solved 2 full questions in OA(2 and 4) which was conducted on 20 Aug.
In the interview first I was asked to solve any of the 2 coding questions among which I managed to solve one fully (very basic array traversal) and the other I was trying which I think is greedy and he stopped me even though there were 15min left and took screenshot and said it's okay and asked to explain the solved question and I did.
Next he looked at the resume and asked if I alone built the projects I mentioned and I said yes. Then he asked me to explain full architecture and flow of how frontend – backend – db work together, I started answering like frontend action triggers request which is caught and processed by express initially running auth middleware and sending appropriate response, he the stopped me and asked to write code for how request is generated on the frontend I just said let's say in login page user clicked on login button react runs onClick function which we pass and generates a request, then he asked me to write that code I thought for a second and initially wrote app.get() something like that and quickly realized that was express code which would be on backend after a cross question and then he again asked how is request sent and using what I thought for a second and told axios and said it was a js library, he again asked me to code I said I don't remember It's been quite some time and then he asked explain auth flow and jwt and again started with flow and when I said username and password sent by user over https tunnel is read by server and it queries db for previously hashed password and it compares and if it matches it will sign a token and send it back and for subsequent requests user will attach the same and ask for resources, he again stopped me asked write code for how server asks mongodb for previously stored hashed password like how does it connect to db, I initially said it will also use internal api to query then he asked how what is it, I thought for a second and said mongoose will be used to connect db and it has inbuilt methods for querying and all he asked to write code which I again said I don't remember.
Then he went to react and asked about types of components in react I only mentioned functional components and couldn't think of any others and then asked what is event capturing i explained about event driven arch like functions are triggered when something is clicked or user does something he said not that and i said don't know and asked about event loop which i explained fully (The only thing I explained properly which had no follow up).
Then he asked let's say a user searches facebook.com how does he receive content, I started explaining first the domain name is sent to dns for ip lookup which uses TLD and and some higher layers for IP address and at any phase if it is cached it is sent back and after receiving the ip, the browser send the request given by frontend to the given ip which can be load balancer or directly server subject to domains architecture, then he stopped me and asked what is TLD and Load balancer and how do they work I explained them and then whatever query is sent the user is first authenticated and then given appropriate response. Somewhere in the middle I also explained CORS and same origin policy enforced by the browser so other malicious websites cannot initiate api calls from other sites.
Since he kept asking code implementation of the flow in project I said sir It's been very long since i touched any dev since placements started I started focusing more on DSA, if I spend a few days with dev I'll get on track.
He asked what is the difference between library and framework, I said using framework means following guidelines the they generally requires where as library is like a set of tools we pick up what we want and use it, basically in case of framework it is in control contrary to a library. then he asked what is nodejs this is where I fucked up and said it is a framework around js which has many inbuilt modules which we can use without us having to write everything from scratch.
And then cpu vs ram i explained and then he asked they why not storage I said ram faster frequent access and mentioned even smaller units which are even faster reside in cpu itself like l1,l2,l3 caches which are in KB's or MB's and so on.
I was mostly explaining by drawing random lines connecting boxes which i labelled frontend, backend and db, he kept asking code and write neatly, since I couldn't write any code sheet was filled with mostly random lines.
Funny thing is there no question regarding OS,CN,DBMS or any other core concept not even introo!!
This is all and he said he's done and asked if I had any questions, atp i was so embarrassed with myself knowing that i couldn't answer many questions and gave some wrong answers I couldn't even ask for feedback, somehow I asked if am able to communicate what i thinking properly and he said yeah and wether whatever you said is correct or not you have to confirm yourself ( tf does that mean!!)
For all the questions there isn't any kind of gesture like if I am right or wrong or anything I'm saying is making sense he just listens and asks a follow up (maybe that is a gesture that i'm wrong somewhere 🥀)
Anyway this is how bad it went, Now guys anyone who got results or knows how we're selected please let tell me what my chances are, will they atleast consider me for dse or straight up rejectt🚶♂️
and btw 200 people attended this recruitment and only single digit l3 shortlisted people.
Source: r/infosys · by /u/MaleficentAd3143