Akshay Gopani - OpenGenus IQ: Learn Algorithms, DL, System Design

Find height or depth of a binary tree

Length of the longest path from the root node to a leaf node is the height of the binary tree. We find it in linear time using a recursive algorithm

Software Engineering

Working with Set in Java like a master

Set is a data structure that is used as a collection of objects. Java supports it through its Java Collection library.

Problems on Binary Tree

Copy a binary tree where each node has a random pointer

We explored an algorithm to copy a binary tree with an additional pointer which points to any random node in the tree. We explored two techniques Naive solution using 2 traversals and Efficient solution using hashing.

Algorithms

Find Maximum Subarray Sum using divide and conquer

We are interested in to find maximum subarray sum (contiguous) of given 1-D array. Array may contain negative and positive numbers which makes this a difficult problem. Brute force will take O(N^2) time while a divide and conquer approach will take O(N log N) time.

Algorithms

Converting Postfix to Infix using Stack

We have explored an algorithm to convert a Postfix expression to Infix expression using Stack. This takes linear time O(N)

Data Structures

Count inversions in an array using Fenwick Tree

Fenwick tree is usually used for range query problems but it can be used to solve the problem of finding the number of inversions in an array efficiently.

Data Structures

Understanding Fenwick tree (Binary Indexed Tree) with Range product

Fenwick tree is a tree based data structure that is widely used to solve range query problems in logarithmic time O(log N) which would otherwise have taken linear time O(N). In this article, we have explained it in depth using the range product query problem.

Problems on Binary Tree

Learn how to traverse a Binary Tree (Inorder , Preorder , Postorder)

In this article we will learn three Depth first traversals namely inorder, preorder and postorder and their use. These three types of traversals generally used in different types of binary tree. In summary, Inorder: left, root, right; Preorder: root, left, right and Postorder: left, right, root