Problem Statement Given a linked list, swap every two adjacent nodes and return its head. You may not modify the...

Problem Statement Given an array nums of n integers, are there elements a, b, c in nums such that a...

Problem Statement Given an array nums of n integers and an integer target, find three integers in nums such that...

Problem Statement Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M.

Problem Statement Write a function to find the longest common prefix string amongst an array of strings.

Problem Statement Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value...

Problem Statement Given n non-negative integers a1, a2, …, an , where each represents a point at coordinate (i, ai)....

Problem Statement Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward...

Problem Statement Given a linked list, remove the n-th node from the end of list and return its head.

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This problem is a simple mathematical calculation. Lets start deriving some equations. Note: Here we are talking about the round...

Problem Statement Implement atoi which converts a string to an integer. ``` Example 1: Input: “42” Output: 42

Problem Statement Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward...

Problem Statement The string “PAYPALISHIRING” is written in a zigzag pattern on a given number of rows like this: (you...

Problem Statement Given a signed integer, reverse digits of an integer.

Problem Statement Given a string s, find the longest palindromic substring in s. You may assume that the maximum length...

Problem Statement There are two sorted arrays nums1 and nums2 of size m and n respectively. Find the median of...

Problem Statement Given a string, find the length of the longest substring without repeating characters.

Problem Statement You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order...

A number consists of digits. Example: 843. Its a 3-digit number. Radix sort, start by sorting numbers first by their...

Counting sort runs on relatively smaller set of input. Counting sort calculates, for every element in array - X, the...

Young Tableau A a X b matrix is Young Tableau if all rows(from left to right) and columns(from top to...

Min Priority Queue is a data structure which manage a list of keys(values). And, gives priority to element with minimum...

Max Priority Queue is a data structure which manage a list of keys(values). And, gives priority to element with maximum...

Problem Statement Given an array of integers, return indices of the two numbers such that they add up to a...

This is another very useful sorting algorithm based on Heap data structure. Read more about Heap Data Structure

Its a tree based data structure which is a complete binary tree(all nodes have 2 nodes, leaf-child may not have...

Sorting Problems Merge Sort Quick Sort Heap Sort Bubble Sort Selection Sort Insertion Sort Count Sort Radix Sort

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Problem Statement You are given an array of integers. And, you have find the range of indexes or sub-array from...

This algorithm is very useful for large input. And, is quite efficient one. It has several implementation, and it is...

** Inversion There is an array(a) and two indexes i and j. Inversion is the element for whom i <...

This algorithm is very efficient one, and is classic example of Divide and Conquer algorithms.

This is kind of preliminary technique of sorting. And, this is the first algorithm that a beginner learns.

Big-O notation In simpler terms, its kind of a unit to measure how efficient an algorithm is, with respect to...

It is one of a simple algorithm to study for a beginner to understanding sorting algorithms.

Its a kind of incremental insertion technique, where the algorithm build up sorting by first sorting n-1 items.

This topic is one of the most common studied. When somebody started preparation of coding interviews. Sorting algorithms would in...

Absolute Must Have Below are must have topics that you must know: Algorithms Data Structures Concepts Breadth First Search (BFS)...

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