Josh Software Associate Software Engineer Interview Questions and Answers

Check if binary tree is balanced or not.

• A balanced binary tree has the height of left and right subtrees differ by at most 1.

• Recursively check the height of left and right subtrees and compare.

• Use a helper function to calculate the height of a subtree.

• Time complexity: O(nlogn) for a balanced tree, O(n^2) for a skewed tree.

Detect loops in a linked list.

• Use two pointers, one moving at a faster pace than the other.

• If there is a loop, the faster pointer will eventually catch up to the slower one.

• To detect the start of the loop, reset one pointer to the head and move both pointers at the same pace.

Spring is a framework for building Java applications, while Spring Boot is a tool for quickly creating Spring-based applications.

• Spring provides a comprehensive framework for building Java applications, while Spring Boot is a tool that simplifies and accelerates the process of creating Spring-based applications.

• Spring requires more configuration and setup, while Spring Boot provides a pre-configured environment that re...read more

A program to check if two strings are anagrams of each other.

• Create two character arrays from the input strings

• Sort the arrays

• Compare the sorted arrays to check if they are equal

Using Streams API to filter and map an array of strings

• Create a stream from the array using Arrays.stream()

• Use filter() to select elements that meet a certain condition

• Use map() to transform each element into a new value

• Use toArray() to convert the stream back into an array

REST API is a web service that uses HTTP requests to access and manipulate data.

• REST stands for Representational State Transfer

• It is an architectural style for building web services

• It uses HTTP methods like GET, POST, PUT, DELETE to perform operations on resources

• It is stateless and can be cached

• It returns data in various formats like JSON, XML, etc.