## Postorder Tree Traversal

Given a binary tree, return the post-order traversal of its nodes’ values. For traversing a binary tree in post-order fashion, we must do these three things for every node N

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## Postorder Tree Traversal

## Preorder Tree Traversal

## Inorder Tree Traversal

## LeetCode – Circular Permutation in Binary Representation (Java)

## Check if Binary trees are Symmetric or Not

## How to check if two Trees are Identical or Not?

## LeetCode – Two Sum IV – Input is a BST

## LeetCode – Validate IP Address

## LeetCode – Reverse Words in a String

## Find pair with given difference K in the array

## Find Path with Maximum Gold

## Largest Continuous Sub Array with Zero Sum – Java

## Colorful Number

## LeetCode – Minimum Absolute Difference

## Given an Array of Integers and Target Number, Find Pair having Sum as Target

## Group all anagrams from a given array of Strings

## Towers Of Hanoi Algorithm

## Selection Sort Algorithm

## Quick Sort Algorithm

## Merge Sort Algorithm

## Insertion Sort Algorithm

## Linear or Sequential Search Algorithm

## Bubble Sort Algorithm

## Binary Search Algorithm

a source of knowledge.

Given a binary tree, return the post-order traversal of its nodes’ values. For traversing a binary tree in post-order fashion, we must do these three things for every node N

Given a binary tree, return the pre-order traversal of its nodes’ values. For traversing a binary tree in pre-order fashion, we must do these three things for every node N

Given a binary tree, return the inorder traversal of its nodes’ values. For traversing a binary tree in in-order fashion, we must do these three things for every node N

Given 2 integers n and start. Your task is return any permutation p of (0,1,2…..,2^n -1) such that : p[0] = start p[i] and p[i+1] differ by only one bit

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).Return 0 / 1 ( 0 for false, 1 for true ) for this

Given two binary trees, write a function to check if they are equal or not. “Two binary trees are considered equal if they are structurally identical and the nodes have

Given a Binary Search Tree and a target number, return true if there exist two elements in the BST such that their sum is equal to the given target. Example

Write a function to check whether an input string is a valid IPv4 address or IPv6 address or neither. IPv4 addresses are canonically represented in dot-decimal notation, which consists of

Given an input string, reverse the string word by word. Example 1: Input: “the sky is blue” Output: “blue is sky the” Example 2: Input: ” hello world! ” Output:

Given an array A of integers and another non-negative integer K, find if there exist 2 indices i and j such that A[i] – A[j] = K, i != j.

In a gold mine grid of size m * n, each cell in this mine has an integer representing the amount of gold in that cell, 0 if it is

Find the largest continuous sequence in an array which sums to zero. Example: Input: { 1 , 3 , -1 , 2 , -4 , 1} Output: {3 , -1

For Given Number N find if its COLORFUL number or not Number is COLORFUL number if product of every digit of a contiguous subsequence is different. A number can be

Given an array of distinct integers arr[], find all pairs of elements with the minimum absolute difference of any two elements. Return a list of pairs in ascending order(with respect

Given an array of integers A[], find two numbers such that they add up to a specific target number B. The program should return indices of the two numbers such

Given an array of strings, return all groups of strings that are anagrams. Represent a group by a list of integers representing the index in the original list. Look at

Towers Of Hanoi Algorithm The towers of hanoi is a mathematical puzzle. We have three towers (or rods or pegs), and a number of disks of different sizes which can

Selection Sort Algorithm Selection sort is a sorting algorithm, specifically an in-place comparison sort. It has O(n2) time complexity, making it inefficient on large lists, and generally performs worse than

Quick Sort Algorithm Quick sort (sometimes called partition-exchange sort) is an efficient sorting algorithm. It is a commonly used algorithm for sorting. When implemented well, it can be about two

Merge Sort Algorithm Merge sort algorithm is an efficient, comparison-based sorting algorithm. Most implementations produce a stable sort, which means that the implementation preserves the input order of equal elements

Insertion Sort Algorithm Insertion sort algorithm is a simple sorting algorithm that builds the final sorted array (or list) one item at a time. It is much less efficient on

Linear or Sequential Search Algorithm Linear or sequential search algorithm is a method for finding a target value within a list. It sequentially checks each element of the list for

Bubble Sort Algorithm Bubble sort algorithm, sometimes referred to as sinking sort, is a simple sorting algorithm that repeatedly steps through the list to be sorted, compares each pair of

Binary Search Algorithm Binary search algorithm requires already sorted collection. Binary search, (also known as half-interval search, logarithmic search, or binary chop) is a search algorithm that finds the position