10+ BNY Software Developer Interview Questions and Answers

Count the total number of palindromic substrings in a given string.

• Iterate through each character in the string and expand around it to find palindromic substrings.

• Use dynamic programming to store the results of subproblems to avoid redundant calculations.

• Consider both odd and even length palindromes while counting.

• Example: For input 'abbc', the palindromic substrings are ['a', 'b', 'b', 'c', 'bb'], totaling 5.

Find the minimum number of taps needed to water the entire garden with given tap ranges.

• Iterate over each tap and find the maximum range it can cover.

• Sort the taps based on their starting point and ending point.

• Use a greedy approach to select the taps that cover the maximum range possible.

Detect if a singly linked list forms a cycle by checking if a node's next points back to a previous node.

• Use Floyd's Cycle Detection Algorithm to determine if there is a cycle in the linked list.

• Maintain two pointers, one moving at twice the speed of the other, if they meet at some point, there is a cycle.

• If one of the pointers reaches the end of the list (null), then there is no cycle.

Sort strings based on custom hierarchy

• Create a mapping of each character to its hierarchy value

• Sort the strings based on the hierarchy value of their first character

• If the first characters have the same hierarchy value, move to the next character

• Repeat until all strings are sorted

Compiler translates entire code into machine code while interpreter translates line by line.

• Compiler converts source code into executable code without executing it.

• Interpreter converts source code into machine code line by line and executes it.

• Compiler generates error messages after the entire code is compiled.

• Interpreter generates error messages as soon as it encounters an error in the code.

• Examples of compilers are GCC, Clang, and Visual C++. Examples of interpreters are Py...read more

Different types of joins and a SQL query.

• Types of joins: Inner join, Left join, Right join, Full outer join, Cross join

• Inner join returns only the matching rows from both tables

• Left join returns all rows from the left table and matching rows from the right table

• Right join returns all rows from the right table and matching rows from the left table

• Full outer join returns all rows from both tables

• Cross join returns the Cartesian product of both tables

• Example query: SELECT * FROM...read more

Heap is a region of memory used for dynamic memory allocation.

• Heap is managed by the operating system or runtime environment.

• It allows for allocation and deallocation of memory at runtime.

• Heap can become fragmented over time, leading to performance issues.

• Examples include malloc() and new() in C++.

Abstraction is the concept of hiding complex implementation details and showing only the necessary features to the user.

• Abstraction in real life: A car dashboard hides the internal workings of the car and only displays necessary information like speed, fuel level, and temperature.

• Abstraction in code: Using abstract classes or interfaces in object-oriented programming to define a blueprint for classes to implement.

• Example code: abstract class Shape { abstract void draw(); } cl...read more

Growth refers to the process of development and improvement over time.

• Growth can be personal, professional, or organizational.

• It involves learning new skills, gaining experience, and expanding one's knowledge.

• Examples include career advancement, skill development, and business expansion.

Hashing is a process of converting data into a fixed-size output using a mathematical function.

• Hashing is used for data integrity and security purposes.

• Hash functions are one-way functions, meaning it is difficult to reverse engineer the original data from the hash value.

• Hashing is used in password storage, digital signatures, and data comparison.

• Examples of hash functions include MD5, SHA-1, and SHA-256.

I have worked on various projects including a web application for a retail company and a mobile app for a fitness startup.

• Developed a web application using React and Node.js for a retail company to manage their inventory and sales.

• Created a mobile app using React Native for a fitness startup to track workouts and progress.

• Collaborated with a team to build a chatbot using Dialogflow and Node.js for a healthcare company.

• Implemented a RESTful API using Express.js and MongoDB for...read more

A palindrome of a string is a word, phrase, number, or other sequence of characters that reads the same forward and backward.

• Check if the string is equal to its reverse to determine if it is a palindrome.

• Ignore spaces and punctuation when checking for palindromes.

• Examples: 'racecar', 'madam', 'A man, a plan, a canal, Panama!'

Insertion sort is a simple sorting algorithm that builds the final sorted array one item at a time.

• Start from the second element and compare it with the elements before it, moving elements to the right until finding the correct position.

• Repeat this process for each element in the array until the entire array is sorted.

• Example: For an array ['3', '1', '4', '1', '5', '9', '2', '6'], the insertion sort steps would be: ['1', '3', '4', '1', '5', '9', '2', '6'] -> ['1', '1', '3', '...read more

Normalization in DBMS is the process of organizing data in a database to reduce redundancy and improve data integrity.

• Normalization involves breaking down a database into smaller, more manageable tables and defining relationships between them.

• It helps in reducing data redundancy by storing data in a structured and organized manner.

• Normalization also helps in improving data integrity by ensuring that data is consistent and accurate.

• There are different normal forms such as 1NF,...read more

Merge sort is a divide and conquer algorithm that divides the input array into two halves, sorts them recursively, and then merges them back together.

• Divide the array into two halves

• Recursively sort each half

• Merge the sorted halves back together

KMP Search Algorithm is a string searching algorithm that finds occurrences of a word within a main text.

• KMP algorithm is based on the idea of pre-processing the pattern to avoid unnecessary comparisons.

• It uses a prefix function to determine the longest proper prefix of the pattern that is also a suffix.

• This allows the algorithm to skip characters in the text that cannot be part of the pattern, improving efficiency.