Amazon Interview Experience for SDE Summer Internship

Round 1:

Date: 28-30 July 2022

Duration: 90 minutes

Problems: 3

1. Longest Decreasing Subsequence Approach:

• Initially considered the brute force approach.
• Then attempted the Longest Increasing Subsequence (LIS) method, which was previously solved.
• Finally, implemented the Dynamic Programming approach for Longest Decreasing Subsequence (LDS).

2. Next Greater Element

3. Third Question (Not remembered.)

Round 2 – Interview Round:

Date: 5 August 2022

Duration: 60 minutes

Problems: 2

Time: Morning 10 AM

Interviewer: Friendly, provided continuous hints.

1. Students’ Position in Row Problem: Given an input of weights of children, find the position of a child such that all students lighter to him are on his left, and the ones heavier than him are on his right. Input: 56 54 63 74 69 Output: 3
2. Transform BST to Greater Sum Tree Approach:

• First wrote the post-order traversal of the input.
• Then performed post-order traversal and did swapping in between to transform the Binary Search Tree (BST) to a Greater Sum Tree.

Round 3:

Duration: 45 minutes

Problems: 2

Interviewer: Friendly, provided various hints.

Topic: Complex coding questions on Tree Data Structures.

1. Time to Burn Tree Approach:

• Initially thought of DFS and BFS approaches but later attempted using a heap, which was not successful.

1. Distance Between Nodes of a Binary Tree Approach: Not mentioned or couldn’t come up with any approach due to time constraints.

Result: Rejected.

Overall, it seems that you went through several rounds of coding interviews with different problem topics and durations. While you were able to solve some questions using different approaches, there were a few challenges and time constraints in the later rounds. Don’t be disheartened by rejection; it’s an opportunity to learn and improve for future interviews! Keep practicing and honing your problem-solving skills.