Hackerrank

Comparison Sorting Quicksort usually has a running time of , but is there an algorithm that can sort even faster? In general, this is not possible. Most sorting algorithms are comparison sorts, i.e. they sort a list just by comparing the elements to one another. A comparison sort algorithm cannot

Each time Sunny and Johnny take a trip to the Ice Cream Parlor, they pool their money to buy ice cream. On any given day, the parlor offers a line of flavors. Each flavor has a cost associated with it. Given the value of  and the  of each flavor for

Alice is taking a cryptography class and finding anagrams to be very useful. We consider two strings to be anagrams of each other if the first string's letters can be rearranged to form the second string. In other words, both strings must contain the same exact letters in

A prime is a natural number greater than  that has no positive divisors other than  and itself. Given  integers, determine the primality of each integer and print whether it is Prime or Not prime on a new line. Note: If possible, try to come up with an  primality algorithm, or

You are given  queries. Each query is of the form two integers described below: -  : Insert x in your data structure. -  : Delete one occurence of y from your data structure, if present. -  : Check if any integer is present whose frequency is exactly . If yes, print 1 else 0.

Harold is a kidnapper who wrote a ransom note, but now he is worried it will be traced back to him through his handwriting. He found a magazine and wants to know if he can cut out whole words from it and use them to create an untraceable replica of

Two strings are anagrams of each other if the letters of one string can be rearranged to form the other string. Given a string, find the number of pairs of substrings of the string that are anagrams of each other. For example , the list of all anagrammatic pairs is  at

A left rotation operation on an array shifts each of the array's elements  unit to the left. For example, if  left rotations are performed on array , then the array would become . Given an array  of  integers and a number, , perform  left rotations on the array. Return the updated

You are given an unordered array consisting of consecutive integers  [1, 2, 3, ..., n] without any duplicates. You are allowed to swap any two elements. You need to find the minimum number of swaps required to sort the array in ascending order. For example, given the array  we perform the

Comparators are used to compare two objects. In this challenge, you'll create a comparator and use it to sort an array. The Player class is provided in the editor below. It has two fields: 1. : a string. 2. : an integer. Given an array of  Player objects, write a