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00: Tree from a list & flattening it back to a list in Java

Hierarchical data with parent & child relationships are very common, and Java collection does not have a Tree data structure, hence it is a popular interview question. Further questions include tree …



01: Tree flattening example in Java

Q. Traverse the tree in depth and return a list of all passed nodes. It should handle different data types as Double, String, etc. The4 interface for the tree node is …



02: Tree structure – calculate average recursively & iteratively in Java

Q. Complete the following “TreeProcessingImpl” class ….. so that the unit tests shown below pass? Skeleton Code



03: Tree traversal algorithms in Java

Q1. What are the different binary tree traversal mechanisms? A1. Traversing a tree means visiting all the nodes of a tree in order. Many different binary tree algorithms involve traversals. For …



03: Understanding Big O notations

Q. Have you seen job advertisements requiring Java candidates to work in real-time or high volume transaction processing systems? If you are applying for such jobs, you can be quizzed on Big O notation. Here …



04: Tree – Get root to leaf max sum in Java example

Q. Write code to traverse a tree and get the largest “root-to-leaf sum”? A “root-to-leaf sum” is a sum of the node values in a root-to-leaf path.



05: Is it a valid binary search tree (BST) ?

Q. Write code test if a given tree is a binary search tree (i.e. BST)? A. A binary search tree (BST) is a binary tree where each node satisfies the following …



06: Binary Tree – Sum Levels Java Example

Q. Write code to traverse a tree and return the sum of the values (Node.getValue()) of all nodes at the level N in the binary tree?



06: Binary Tree – Get root to leaf max sum in Java example

Q. Write code to traverse a binary tree and get the largest “root-to-leaf sum”? A “root-to-leaf sum” is a sum of the node values in a root-to-leaf path.



07: Tree – Sum Levels Java example

Q. Write code to traverse a tree and return the sum of the values (Node.getValue()) of all nodes at the level N in the tree?



08: Part-1: Basic Java Tree structure interview questions and coding questions

Java does not have a Tree class but you can define one. In my 10+ years as a Java developer, I have rarely used a Tree structure,  but when I do …



09: Part 2: Java Tree structure interview questions and coding questions

In the previous post entitled  Java Tree structure interview questions and coding questions — Part 1, we looked at a very simple Tree structure. In this example, let’s look at a …



09: When to use which Java data structure? and why?

List, Set, Map, and Queue(access the ends FIFO or LIFO) are the basic Java data structure interfaces for which there are different implementations to cater for different usage patterns. Java data …



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