Amazon Interview experience | Set 329 (Off-Campus for SDE-1)

I applied off campus for Amazon Bangalore SDE-1. It started with two face to face rounds. Face-2-Face (Round 1) :

1. A binary tree is given print the binary tree in vertical order. I gave him a hashmap based approach then he said can you improve it and finally I came up with space optimized solution using DLL.

2. He asked do you like DP. I said yes so He asked me a puzzle. There is a stream of integers and two players are playing. Each player can take one integer from either of the corners. I need to tell if player A is playing first then what will be his maximum score. I gave him recursive approach he said its perfectly fine. He asked me to optimize my solution cause it was exponential finally I gave him a dp approach he was satisfied and then told me to write full bug free code for the same.

3. N number of identical nodes are given. You need to calculate how many no of binary trees are possible?

Face-2-Face (Round 2): He started introducing himself and then asked me some behavioural questions.

1. Tell me about yourself.
2. Your industry experience.
3. Why do you want quit so early?
4. What courses you did?

And then he asked me one dynamic programming question. A matrix is given and each cell has some value. You can enter from any cell of first row and make three different moves down, south-east and south-west i.e. from (i,j) to (i+1,j+1), (i+1,j-1),(i+1,j). You need to calculate maximum value when you reach last row. I gave recursive solution of complexity O(3^n) and then finally gave him dynamic programming solution in O(n^2). He was not done yet then he asked me to print the path as well. I did. Both interviews were good so I was waiting for results. After 2 days I got the call you have cleared both the rounds and they want to conduct two more rounds. Next step was two more face-2-face rounds.  Face-2-Face (Round 3): It was a bar raiser round very crucial for the whole process. Interviewer introduced himself and asked me behavioural questions like:

1. Tell me about yourself.
2. Interests, strengths and weekness.
3. Then he asked me about my final year project which was based on Machine Learning. He discussed everything in details. After that he asked me about office life and working culture etc.

I was currently working on Blockchain so he asked me about this technology cause its totally new and amazing tech so he was pretty impressed. He asked if I have any question for him. I asked several question related to his work and Amazon visions. Face-2-Face (Round 4): Hiring manager round This round was behavioural round and cultural fit. He asked so many questions related to projects and current work.

1. Why do you want to join Amazon?
2. Why are you quitting?
3. What are your future expectations?

Then he asked me explain current company project and project architecture, my role in team etc. Guys prepare well for behavioural questions, they look for culture fit. Coding question: Print the vertical sum of a binary tree. Result : I got the call after 3 days and hr said congratulations, you are placed and It was like dream came true. Thanks to my parents, Upendra Bhaiya and Prajakta for all the support. I want to thank geeksforgeeks team, it’s an ideal platform for preparing coding interviews.