Amazon Senior Engineer Interview Questions and Answers

Test contains 26 questions for me 13 are java based 13 are c++ based

Q1. Indexing in dbms
Ans. 
Indexing in DBMS is a technique to improve the performance of queries by creating a data structure that allows for faster retrieval of data.
• Indexes are created on columns in a database table to speed up the retrieval of rows that match a certain condition.

• Types of indexes include clustered, non-clustered, unique, and composite indexes.

• Examples of indexing techniques include B-tree, hash, and bitmap indexes.

• Indexing can...read more
Answered by AI
Add your answer
Q2. Find whether two strings are or not anagrams
Ans. 
Check if two strings are anagrams by comparing the sorted characters in each string.
• Sort the characters in both strings and compare if they are equal.

• Ignore spaces and punctuation when comparing the strings.

• Example: 'listen' and 'silent' are anagrams.

• Example: 'hello' and 'world' are not anagrams.
Answered by AI
View 1 more answer

Q1. Inorder traversal without recursion
Ans. 
Use a stack to simulate the recursive inorder traversal process
• Create an empty stack to store nodes

• Start with the root node and push it onto the stack

• While the stack is not empty, keep traversing left and pushing nodes onto the stack

• Once you reach a leaf node, pop it from the stack, print its value, and move to its right child

• Repeat the process until all nodes have been visited
Answered by AI
Add your answer
Q2. How to make a class final
Ans. 
To make a class final, use the 'final' keyword in the class declaration.
• Use the 'final' keyword before the 'class' keyword in the class declaration

• A final class cannot be subclassed or extended

• Final classes are often used for utility classes or classes that should not be modified
Answered by AI
Add your answer

Q1. Print the nodes of a n-ary tree in an arc wise manner as seen from the outside.
Ans. 
Print nodes of n-ary tree in arc wise manner from outside
• Traverse the tree level by level from outside to inside

• Use a queue to keep track of nodes at each level

• Print the nodes at each level in a clockwise or anticlockwise manner
Answered by AI
Add your answer

Q1. Data structure and algorithm
Add your answer
Q2. Some tricky logical question
Add your answer
Q3. Stack and queue
Add your answer
Q4. Some basic question about system Design
Add your answer

Hackerrank Coding Test, Leetcode medium questions

HLD test, was asked to design an online coding platform like leetcode

Q1. Most interesting project you have worked on
Add your answer
Q2. How do you handle conflict at workplace
Add your answer

Some database questions,some java questions .

Q1. What is the difference between javascript and jQuery.
Ans. 
JavaScript is a programming language used for web development, while jQuery is a library built with JavaScript to simplify HTML document traversal and manipulation.
• JavaScript is a programming language, while jQuery is a library written in JavaScript.

• JavaScript can be used for a wide range of tasks, while jQuery is mainly used for DOM manipulation and event handling.

• JavaScript is a core technology for web development, w...read more
Answered by AI
Add your answer
Q2. Define different types of join
Ans. 
Different types of joins are used in SQL to combine rows from two or more tables based on a related column between them.
• Inner Join: Returns rows when there is at least one match in both tables.

• Left Join (or Left Outer Join): Returns all rows from the left table and the matched rows from the right table.

• Right Join (or Right Outer Join): Returns all rows from the right table and the matched rows from the left table.

• Full ...read more
Answered by AI
Add your answer
Q3. Define multithreading concept and exception handling.
Ans. 
Multithreading allows multiple threads to run concurrently, while exception handling deals with errors in a program.
• Multithreading involves running multiple threads simultaneously to improve performance and responsiveness.

• Threads share the same memory space but have their own program counter and registers.

• Exception handling is a mechanism to handle errors or exceptional situations in a program.

• It helps prevent the prog...read more
Answered by AI
Add your answer

Q1. Tell me about yourself
Add your answer

Q1. Given array of integer create subarray with sum = 0
Ans. 
Create subarrays with sum = 0 from given array of integers.
• Iterate through the array and keep track of the running sum.

• Store the running sum in a hashmap and check if the current sum - any previous sum equals 0.

• If yes, then the subarray between those two indices has a sum of 0.
Answered by AI
Add your answer
Q2. Left view of binary tree
Ans. 
The left view of a binary tree is the set of nodes visible when the tree is viewed from the left side.
• Traverse the tree in a level order manner and keep track of the first node at each level.

• Use a queue to store nodes at each level and update the left view nodes accordingly.

• Example: For a binary tree with root node 1, left child 2, and right child 3, the left view would be [1, 2].
Answered by AI
Add your answer