Algorithms that run our Universe

Zig Zag Traversal of Binary Tree

In this article, we present 4 different approaches for Zig Zag Traversal of Binary Tree using stack, deque, recursion and an iterative approach.

Algorithms

Check if 2 Binary Trees are isomorphic

Two Binary Trees are known as isomorphic if one of them can be obtained from the other one by series of flipping of nodes, swapping the children both left and right of number of nodes.

Algorithms

Convert Binary Tree to Circular Doubly Linked list

To convert binary tree to circular doubly linked list, we will take left node as previous pointer and right node as next pointer. The order of nodes in Doubly Linked List must be same as in inorder of the given binary tree.

Algorithms

Succinct (0-1) Encoding of Binary Tree

Succinct (0-1) Encoding of Binary Tree is an approach to encode a Binary Tree to the lowest possible space and maintain the structural information.

Algorithms

LCA in Binary Tree using Euler tour and Range Minimum Query

In this problem, we will find the Lowest Common Ancestor of a Binary Tree using Euler tour and Range Minimum Query. We can solve the LCA problem by reducing it to a RMQ problem.

Algorithms

Lowest Common Ancestor in a Binary Tree

In binary trees, for given two nodes a and b, the lowest common ancestor is the node of which both a and b are descendants. We explored the algorithm to find Lowest Common Ancestor in a Binary Tree.

Problems on Binary Tree

Operations in Threaded Binary Tree

There are three main operations which can be done on a threaded binary tree Insert, Search and Delete operation which we have explained in depth.

Problems on Binary Tree

Threaded Binary Tree

Threaded binary tree is a simple binary tree but they have a speciality that null pointers of leaf node of the binary tree is set to inorder predecessor or inorder successor.

Algorithms

Boolean Parenthesization Problem

We will solve Boolean Parenthesization Problem using Dynamic Programming and understand the algorithm with a step by step explanation. The time complexity to solve this problem is O(N^3) with a space complexity of O(N^2).

Algorithms

Delete Middle Node from Linked List

In this problem, we will delete the Middle Node from a given Linked List. We have covered the algorithm (along with implementation) to delete the middle node from a Singly Linked List and Doubly Linked List.

Problems on Binary Tree

Checking if a Binary Tree is foldable

A binary tree is foldable if the left subtree and right subtree are mirror images of each other. An empty tree is also foldable. We have presented two algorithms to check if Binary Tree is foldable.

Problems on Binary Tree

Serialization and Deserialization of Binary Tree

We have presented the process of Serialization and Deserialization of Binary Tree where we convert a Binary Tree into a compress form which can be saved in a file and retrieved back.

Problems on Binary Tree

Convert a Binary Tree to a Skewed Binary Tree

We have presented the algorithm to Change a Binary Tree to a Skewed Binary Tree (both Increasing Skewed Binary Tree and Decreasing Skewed Binary Tree).

Problems on Binary Tree

Check if a Binary Tree is skewed or not

We have presented the algorithm to check if a given Binary Tree is skewed or not (can be left or right skewed Binary Tree).

Problems on Binary Tree

Introduction to Skewed Binary Tree

A binary tree can be called a skewed binary tree if all nodes have one child or no child at all. There are two types: left and right skewed.

Algorithms

Munchausen Number

A number that is equal to the sum of its digits each raised to the power equal to its digit is a Munchausen Number or perfect digit-to-digit invariant(PDDI).

Problems on Binary Tree

Find ancestors of a given node in a binary tree (Recursive + Iterative)

Understand how to find ancestors of a given node in a binary tree recursively and iteratively in linear time O(N).

Problems on Binary Tree

Find nodes which are at a distance k from root in a Binary Tree

We are given the root of a tree, and an integer k. We need to print all the nodes which are a distance k from the root.

Problems on Binary Tree

Find ancestors of a node in Binary tree (Recursive)

In this problem, we are given a binary tree and a key k. We need to find out all the ancestors of node k. We have used a recursive approach.

Algorithms

Fractional Cascading in Binary search

Fractional Cascading is an optimization over Binary Search to perform Binary Search on K sorted lists to improve the time complexity from O(K logN) to O(logN + K). In this article, fractional cascading in binary search will be covered.

Algorithms

Knight’s Tour Problem

The Knight's Tour Problem is one of the famous problem in which we have the knight on a chessboard. The knight is supposed to visit every square exactly once. We have explored Backtracking and Warnsdorff's algorithm.

Algorithms

Finding nodes at distance K from a given node

We have discussed the approach to find out the nodes at k distance from the given node. There are two approaches: one using Breadth First Traversal and other using Percolate Distance.

Algorithms

Move Last Element of Linked List to Front

We will explore recursive and iterative algorithm to Move Last Element of Linked List to Front.

Software Engineering

Elementary Cellular Automaton and Its Applications in Computer Science

This article explains 1-Dimensional Elementary Cellular Automaton, and its applications, and mathematical explanation of concept behind with code in python.

Dynamic Programming (DP)

Longest Palindromic Subsequence (using Dynamic Programming)

Longest palindrome subsequence problem (LPS) is the problem to find the length of longest subsequence in a string that is a palindrome. This can be done using Dynamic Programming in O(N^2) time.