Background: B.Tech ECE
Work Experience: 1.5+ years as Software Engineer in Service based company
Position: SDE-1 Amazon
Location: Bangalore, India
Interview Period: Feb - Mar 2021
Total rounds: 1 OA + 4 Tech Rounds

Interview Process:

Round 0: Online Coding Assessment - Feb, 2021

• Got a Hackerrank test link for OA Round.
• 2 coding challenge questions - 90 min
  1. Reorder Data in Log Files
  2. Similar Problem . Given a 2D Matrix, starting point(top left corner) and destination point. The 2D matrix contains obstacles marked as 'D', other areas as 'O' and the destination as 'X'. Find the shortest path to reach the destination.
• Write down the approach of your coding solution for both questions(15 min)

Rest of the rounds started with basic intro and project discussion which went for 20-30 mins.

Round 1: DS & Algo Round - Feb, 2021 (1 hour)

• Intro and projects - 20 mins
• Word Search - II
• Interviewer asked to discuss the approach and then code. Few questions on the traversal techniques (DFS/ BFS). Which traversal is better for this problem and justify your answer? Time complexity of both the traversals and overall time complexity of my approach
• 1 Leadership question

Round 2: Problem Solving Round - Feb, 2021 (1 hour)

• Projects discussion and a question - which is the most frequently used data structure in databases?
• Gave a problem related to Binary Tree - Given a Binary tree mentioned below. Remove redundant connection from Binary Tree. Eg: Node 0 is connected to 2 and 4 both

				3
			 /     \
		  2          4
	  /    \      /    \
    1	      0         5

• Follow up question - Assume the tree as a Binary Search Tree & was asked to solve it.

Round-3: Managerial Round - Mar, 2021 (1 hour)

• Intro & Project Discussion - 20 mins
• Design a Timer using recursion.
• Logical question - Given 27 balls of which 1 ball is defective (has less weight). Given an electronic weighing machine & 3 chances to utilize it. Find the defective ball within the given chance limit.
• Merge Sort - Explanation and applications

Round-4: Bar Raiser Round - Mar, 2021 (1 hour)

• Project discussion & Basic CS questions - ACID properties, Singleton Class & basic questions related to technologies that I previously worked on.
• LP questions - Time when you were not able to meet your deadline? Time when you earned your manager's trust?
• Coding Question - similar to this question - Unique File names

HR got back to me with the verdict within 5 days (3 business days) !!

Bonus Tips:

• Make the interview more like a discussion
• Try to speak about your day to day work, skills and projects at least for 15-20 mins
• Practice on explaining the time complexity of your code. Interviewers always expect this.

Compensation: https://leetcode.com/discuss/compensation/1143810/Amazon-SDE-1-or-Bangalore-or-Apr-2021