Amazon Interview Experience | SDE-1 (Off-Campus)
Amazon Interview Experience for SDE – 1 Off campus Drive Hyderabad Location.
2019 passed out.
Round 1:(Online Coding Round)
This is a Hackerearth test, it consist of 20 MCQ majorly form DS, OS, CN and OOPS and few output questions and 2 programming questions.
Above round is of 90 min. After some day I received a mail from HR that I was shortlisted for onsite rounds.
Round 2: (Face to face interview)
In this round 2 questions were asked which I have to be answered in 70 min and also write code for them on paper.
- First question was to reverse the link list with size of K. https://www.geeksforgeeks.org/reverse-a-list-in-groups-of-given-size/
2. Given a array break the array into three sub-array by removing 2 elements of it, in such a way that all three sub-array have same sum. O(n) Time Complexity and O(1) space complexity. eg. A->[1, 1, 1, 4, 2, 1, 5, 3] Output- [1, 1, 1] [2, 1]  here if we remove 4 and 5 we left with 3 sub-array with same sum.
Round 3:(Face to face interview)
In this also 2 questions were asked and also i have to write code for them on paper.
1. Given a string print the largest sub-string containing vowels in even counts.O(n) eg. S-> aqwrteakjeaghev , answer->aqwrteakje as it contain 2 ‘a’ and 2 ‘e’. Second in same question he want me to print all sub-string if multiple sub-strings are possible of same length.
Round 4:(Face to face interview)
Interviewer start with discussion about my current profile work and also with a short discussion on my project(College Project). Then he asked me to design a algo for how to maintain server-load with load Balancer.(Not able to answer it basically he want to answer something like round robin type algorithm.)[This question was ask on the basis of my current work]
Now he jump to coding questions.
- Given a data made up of BST which is dynamic(i.e nodes keep on adding as the user enter new details) he want me to convert that BST to Complete tree.[Have a healthy discussion on it about 10-15 min i gave him solution with rotations like in AVL and ultimately at end he agreed with a solution consist of in-order which run on the Batch basis.].Then he told me to code the function which take tree as input and return root by changing it to complete tree.
- Second he asked for a given a number ‘n’, print how many valid parenthesis strings containing ‘(‘ or ‘)’ are possible of that length. I told its an application of Catalan Number then he want me to write a code to generate nth Catalan number without using formula basically he want me to write the Dynamic version of it. [https://www.geeksforgeeks.org/program-nth-catalan-number/]
Luckily i was able to write both codes in this round and after all 3 onsite rounds HR told me that i also have 1 more round i.e Bar Raiser round and she will share the detail via mail.
Round 5:(Bar Raiser)[On video call]
This round is with a very Senior person having 15+ years of experience, Interview started with his introduction, and then my introduction. Then he asked me my role in my current team and also want me to explain a situation in which i perform something which is completely different from my current role.[This is basically a Behavioural question so answer such question on the basis of there Leadership Principle.]
Then he jump to coding part.
- Given a number in form of link list we have to add one to that number and update the link list accordingly. eg. 123 is store like 1->2->3 and adding 1 to 123 it become 124 so we have to update the list to 1->2->4. O(n) time and with O(1) extra space without reversing without recursion.
- Given a playlist of songs we have to shuffled that playlist.[Basically an application of https://www.geeksforgeeks.org/shuffle-a-given-array-using-fisher-yates-shuffle-algorithm/]
After 2 weeks i received a call from HR saying that Amazon is releasing an offer of SDE1 for me.
- In all rounds you will be asked to write a production level code so be prepared for that.[But In first two round of face to face if your code is not perfect in one go and interviewer found 1, 2 corner cases which may fail in it the you may got a chance to correct it, all depend on the interviewer not sure about 3rd round as in my case i was able to write perfectt code in one go]
- In any round if you stuck, discuss it with interviewer as they definitely help you on that.
- But in the last round i.e with BAR Raiser make sure to write complete code and moreover your code should be production ready i.e if he/she will able to find any case which fail in your code then there will be chance of rejection as he/she only read your code and said ok thats it for the day any questions for me and finished your interview, so make sure to write a perfect code before submitting to him. [As one of my friend got rejected in Bar Raiser as he was not able to complete code]
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