OpenGenus IQ: Learn Computer Science

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.

Software Engineering

Basics of Unordered multiset in C++

An unordered multiset is an unordered set (a set in which a key can be stored in any random order) that allows different elements to have equivalent values (allows duplicate items).

Software Engineering

Basic commands for using VIM editor like a Pro

In this guide, we have presented all basic commands that you will need to use VIM editor for doing all tasks efficiently. You will learn how to search for a word, how to replace the word, select, copy, paste, using various special features of VIM and much more.

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).

Software Engineering

Create a custom UITableView in iOS using Swift

Create an iOS app which has a custom table view (UITableView) using MVC pattern using Swift.

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.

Software Engineering

C++ Likely and Unlikely attributes

C++ likely and unlikely attributes came into existence with the release of C++ 20. In our C++ code if we know which lines of code would most probably be executed during our code execution then we can use likely and unlikely attributes.

Software Engineering

Vector::pop_back() in C++

We have learnt about pop_back() method of Vector class included in std::vector library in C++. Vectors can be considered as dynamic arrays on the basis of its usage.