Amazon Interview Experience | Set 165 (For SDE I)

I received interview call from amazon.com (Bangalore) for SDE1 position for 1.5 year experience. 

Round 1: 1 hour – written test at amazon office.

Q1. Given a set of strings, find the alphabets common to all strings. 
     <I used Hashmaps> 

Q3. Longest Palindronic subsequence in a given string.

Q3. Find LCA of two nodes in a binary tree

Round 2: F2F 1.5 hour 

Given a huge file with large number of words, code a function that would take a word as input and print all anagrams of that word present in the file as output. Function has to be really really fast alsmo O(1) run time. You are allowed to take as much time and resources for pre processing the file once. But after pre-processing function should perform in O(1) time. 

<Use hashmap, and fact that all anagrams have similar alphabetical order of letters> 

Create a hash function for above. 

He then asked, another way instead of Hash ? 

How to optimize searching among this linked list of heads of other linked lists. 

Round 3: F2F 1 hour

Only one question – Print leftmost and rightmost node at every level of binary tree. 

Round 4: F2F 1 hour

Given a string with some ‘?’ where ? can be 0 or 1. Print all possible strings by substituting ? with 0/1. 

Eg: I/p Amaz??n, 
     o/p Amaz00n, Amaz10n, Amaz01n, Amaz11n 

Connect all nodes of a binary tree which are at same level.

Round 5: Telephonic 1.5 hour

Write a code (online shared collab document) to check whether a tree satisfies children-sum property. 

Write a code (online shared collab document) to convert a given tree to a tree that satisfies children-sum property. 

Some questions related to Operating Systems 
Major difference between thread and process 
CPU Scheduling difference between process and threads. 
Necessary and sufficient conditions for a deadlock Deadlock 

Suppose you have a list of 1 billion integers, find 1 million largest integers in this list. 
List can have repatitive elements, max memory limit is 1 million numbers 

Asked to calculate time complexity for my algorithm 

Round 6: F2F 1 hour

Discussion on current work. You must know what you are working on in detail as you would be grilled 

Top 3 features I would put on a website portal if I’m launching a cab service. (Non-technical) 

Write code for scheduling algorithms for such a cab services provided you have a list of future bookings, and list of cabs in your fleet. 
<I was asked to write OOP paradigm code> 

Tips:
Try to interact continuously with interviewer. Keep thinking aloud and keep discussing with interviewers your ideas and approaches 
Prepare Data structures, in particular binary tree very thoroughly. 

Hope this helps. 🙂 

All Practice Problems for Amazon !