Amnex Infotechnologies Java Developer Interview Questions and Answers

Basic aptitude questions

3 basic questions they asked

Pointer and SQL related questions

3 Questions of mid difficulty

2 questions of mid to hard difficulty

Q1. Basic DSA and problem solving related questions
Add your answer
Q2. How to design and implement a dictionary application
Ans. 
Design and implement a dictionary application for easy word lookup
• Define data structure to store words and their meanings

• Implement search functionality to look up words quickly

• Include features like word suggestions, synonyms, and antonyms

• Allow users to add new words and meanings to the dictionary

• Consider implementing a user-friendly interface for easy navigation
Answered by AI
Add your answer

Good and easy learn dsa and algo

Learn dsa and algo binary tree and lists

Q1. Learn basic subjects and topics like OS and Cloud
Add your answer

Q1. Short round based on aptitude and attidtude
Add your answer

Aptitude,reasoning,verbal,C language,Java,C++

Q1. What is interface in JAVA
Add your answer
Q2. Explain OOPS in JAVA
Add your answer

It was an 1hr interview session

Q1. Find the occurrence of each element in an array
Ans. 
Count the occurrence of each element in an array of strings
• Iterate through the array and use a hashmap to store the count of each element

• If element already exists in the hashmap, increment its count by 1

• Return the hashmap with element counts
Answered by AI
Add your answer

Q1. Tell me about yourself
Add your answer

Round duration - 120 minutes
Round difficulty - Medium

Timing was 9: 30 AM. Platform was quite good and easy to understand.

Q1. 
Reverse Only Letters Problem Statement
You are given a string S. The task is to reverse the letters of the string while keeping non-alphabet characters in their original position.
Example:
Input:
S = "...read more
Ans. 
Reverse the letters of a string while keeping non-alphabet characters in their original position.
• Iterate through the string and maintain two pointers, one at the start and one at the end, to reverse only the letters

• Use isalpha() function to check if a character is an alphabet or not

• Swap the letters at the two pointers until they meet in the middle
Answered by AI
Add your answer
Q2. 
Find Duplicates in an Array
Given an array ARR of size 'N', where each integer is in the range from 0 to N - 1, identify all elements that appear more than once.
Return the duplicate elements in any orde...read more
Ans. 
Find duplicates in an array of integers within a specified range.
• Iterate through the array and keep track of the count of each element using a hashmap.

• Return elements with count greater than 1 as duplicates.

• Time complexity can be optimized to O(N) using a set to store duplicates.

• Example: For input [0, 3, 1, 2, 3], output should be [3].
Answered by AI
Add your answer
Q3. 
Pancake Sorting Problem Statement
You are given an array of integers 'ARR'. Sort this array using a series of pancake flips. In each pancake flip, you need to:
Choose an integer 'K' where 1 <= 'K' <...read more
Ans. 
Sort an array using pancake flips and return the sequence of flips made.
• Iterate through the array and find the position of the maximum element in each iteration.

• Perform pancake flips to move the maximum element to the correct position.

• Continue this process until the array is sorted.

• Return the sequence of positions from where flips were made.
Answered by AI
Add your answer
Q4. 
Sum of Digits Problem Statement
Given an integer 'N', continue summing its digits until the result is a single-digit number. Your task is to determine the final value of 'N' after applying this operation ...read more
Ans. 
Given an integer, find the final single-digit value after summing its digits iteratively.
• Iteratively sum the digits of the given integer until the result is a single-digit number

• Output the final single-digit integer for each test case

• Handle multiple test cases efficiently
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Medium

Timing was 9:30 AM. The interviewer was very nice.

Q1. 
Fibonacci Number Verification
Identify if the provided integer 'N' is a Fibonacci number.
A number is termed as a Fibonacci number if it appears in the Fibonacci sequence, where each number is the sum of...read more
Ans. 
Check if a given number is a Fibonacci number or not.
• Iterate through the Fibonacci sequence until you find a number greater than or equal to the given number.

• Check if the given number matches the Fibonacci number found in the sequence.

• If the number matches, output 'YES'; otherwise, output 'NO'.
Answered by AI
Add your answer
Q2. Write an SQL query to find the second highest salary from a table.
Ans. 
SQL query to find the second highest salary from a table
• Use the MAX() function to find the highest salary

• Use the WHERE clause to exclude the highest salary

• Order the salaries in descending order and limit the result to 1
Answered by AI
Add your answer

Round duration - 30 Minutes
Round difficulty - Medium

Timing was 12 PM. Interviewer was not good.

Q1. 
Character Frequency Problem Statement
You are given a string 'S' of length 'N'. Your task is to find the frequency of each character from 'a' to 'z' in the string.
Example:
Input:
S : abcdg
Output:
1...read more
Ans. 
The task is to find the frequency of each character from 'a' to 'z' in a given string.
• Create an array of size 26 to store the frequency of each character from 'a' to 'z'.

• Iterate through the string and increment the count of the corresponding character in the array.

• Print the array of frequencies as the output for each test case.
Answered by AI
Add your answer
Q2. What is normalization and can you explain the concept of Third Normal Form (3NF)?
Ans. 
Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity.
• Normalization is a technique used to organize data in a database efficiently.

• Third Normal Form (3NF) is a level of normalization that ensures that data is stored in a way that prevents certain types of data anomalies.

• In 3NF, every non-prime attribute is fully functionally dependent on the primary key.

• For exampl...read more
Answered by AI
Add your answer

Round duration - 120 minutes
Round difficulty - Easy

Timing was 9: 30 AM. Platform was quite good and easy to understand.

Q1. 
Reverse Only Letters Problem Statement
You are given a string S. The task is to reverse the letters of the string while keeping non-alphabet characters in their original position.
Example:
Input:
S = "...read more
Ans. 
Reverse the letters of a string while keeping non-alphabet characters in their original position.
• Iterate through the string and store the non-alphabet characters in their original positions

• Reverse the letters using two pointers technique

• Combine the reversed letters with the non-alphabet characters to get the final reversed string
Answered by AI
Add your answer
Q2. 
Find the Duplicate Number Problem Statement
Given an integer array 'ARR' of size 'N' containing numbers from 0 to (N - 2). Each number appears at least once, and there is one number that appears twice. Yo...read more
Ans. 
Find the duplicate number in an array of integers from 0 to N-2.
• Iterate through the array and keep track of the frequency of each number using a hashmap.

• Return the number with a frequency greater than 1 as the duplicate number.
Answered by AI
Add your answer
Q3. 
Reverse Array Elements
Given an array containing 'N' elements, the task is to reverse the order of all array elements and display the reversed array.
Explanation:
The elements of the given array need to...read more
Ans. 
Reverse the order of elements in an array and display the reversed array.
• Iterate through the array from both ends and swap the elements until the middle is reached.

• Use a temporary variable to store the element being swapped.

• Print the reversed array after all elements have been swapped.
Answered by AI
Add your answer
Q4. 
Sum of Digits Problem Statement
Given an integer 'N', continue summing its digits until the result is a single-digit number. Your task is to determine the final value of 'N' after applying this operation ...read more
Ans. 
Given an integer, find the final single-digit value after summing its digits iteratively.
• Iteratively sum the digits of the given integer until the result is a single-digit number

• Output the final single-digit integer for each test case

• Handle multiple test cases efficiently
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Easy

Timing was 9:30 AM. The interviewer was very nice.

Q1. 
Nth Fibonacci Number Problem Statement
Calculate the Nth term in the Fibonacci sequence, where the sequence is defined as follows: F(n) = F(n-1) + F(n-2), with initial conditions F(1) = F(2) = 1.
Input:
...read more
Ans. 
Calculate the Nth Fibonacci number efficiently using dynamic programming.
• Use dynamic programming to store and reuse previously calculated Fibonacci numbers.

• Start with base cases F(1) and F(2) as 1, then calculate subsequent Fibonacci numbers.

• Optimize the solution to avoid redundant calculations by storing intermediate results.

• Time complexity can be reduced to O(N) using dynamic programming.

• Example: For N = 5, the 5th F
Answered by AI
Add your answer
Q2. Write an SQL query to find the second highest salary from a table.
Ans. 
SQL query to find the second highest salary from a table
• Use the MAX() function to find the highest salary

• Use the NOT IN operator to exclude the highest salary from the results

• Order the results in descending order and limit the query to return only the second row
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Medium

Timing was 12 PM. Interviewer was not good.

Q1. 
Character Frequency Problem Statement
You are given a string 'S' of length 'N'. Your task is to find the frequency of each character from 'a' to 'z' in the string.
Example:
Input:
S : abcdg
Output:
1...read more
Ans. 
The task is to find the frequency of each character from 'a' to 'z' in a given string.
• Create an array of size 26 to store the frequency of each character from 'a' to 'z'.

• Iterate through the string and increment the corresponding index in the array for each character encountered.

• Print the array of frequencies as the output for each test case.
Answered by AI
Add your answer
Q2. What is normalization and can you explain the concept of Third Normal Form (3NF)?
Ans. 
Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity.
• Normalization is a database design technique used to structure a relational database in a way that reduces data redundancy and improves data integrity.

• Third Normal Form (3NF) is a level of database normalization where every non-prime attribute of a table is dependent on the primary key.

• To achieve 3NF, a table m...read more
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Easy

There were two section Aptitude and Coding.

Q1. 
Buy and Sell Stock Problem Statement
Imagine you are Harshad Mehta's friend, and you have been given the stock prices of a particular company for the next 'N' days. You can perform up to two buy-and-sell ...read more
Ans. 
The task is to determine the maximum profit that can be achieved by performing up to two buy-and-sell transactions on a given set of stock prices.
• Iterate through the array of stock prices and calculate the maximum profit that can be achieved by buying and selling at different points.

• Keep track of the maximum profit after the first transaction and the maximum profit overall by considering different combinations of buy a...read more
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Easy

This was the first technical interview.

Q1. 
Pair Sum Problem Statement
You are given an integer array 'ARR' of size 'N' and an integer 'S'. Your task is to find and return a list of all pairs of elements where each sum of a pair equals 'S'.
Note:
...read more
Ans. 
Find pairs of elements in an array that sum up to a given value, sorted in a specific order.
• Iterate through the array and for each element, check if the complement (S - current element) exists in a hash set.

• Keep track of pairs in a hash set to avoid duplicates.

• Sort the pairs based on the criteria mentioned in the question.

• Return the sorted list of pairs.
Answered by AI
Add your answer