Amazon SDE Intern Interview Experience
Summary
My interview consisted of one technical round focusing on DSA fundamentals and problem-solving. I discussed solutions for deep copying a linked list with random pointers and finding the next higher-rated movie, including optimizations and detailed explanations.
Full Experience
The interview consisted of one technical round, focused on DSA fundamentals + problem-solving depth.
Question 1: Deep Copy of Linked List (with Random Pointer)
The interviewer explored the concept in depth.
My Approach:
- First explained brute force using HashMap (O(n) space)
- Then optimized to O(1) space using node interleaving
Follow-ups:
- What do key & value represent? → The original node acts as the key and its copied node as the value.
- Can we do deep copy without extra space? → Yes, using the interweaving technique with O(1) auxiliary space.
- Why separate linked lists? → To ensure changes in the copied list don’t affect the original.
- Dry Run- hashmap solution.
- Optimisation & Time Complexity/ Space Complexity
- Edge cases.
Question 2: Next Higher Rated Movie
Given a list of movies with ratings, find the next movie on the right with a higher rating.
My Approach:
Used Monotonic Stack (Next Greater Element pattern).
Follow-ups:
- Why traverse from right?
- When would brute force fail?
- Can we do it without stack?
It was a concept-heavy and discussion-oriented interview.
Interview Questions (2)
Deep Copy of Linked List with Random Pointer
Deep Copy of Linked List (with Random Pointer). The interviewer explored the concept in depth. Follow-ups included:
- What do key & value represent?
- Can we do deep copy without extra space?
- Why separate linked lists?
- Dry Run- hashmap solution.
- Optimisation & Time Complexity/ Space Complexity
- Edge cases.
Next Higher Rated Movie
Given a list of movies with ratings, find the next movie on the right with a higher rating. Follow-ups included:
- Why traverse from right?
- When would brute force fail?
- Can we do it without stack?
Preparation Tips
I suggest two things:
- You should always have an answer for:
- Why you're using this DS? what advantage that gives in this PS?
- Why you're doing this step?
- Can you optimize this?
- Run me through a test case.
- What's the TC/ SC?
- Think aloud clearly.