Natural numbers are numbers that start from 1 and include all the positive integers. The following article discusses two possible approaches to compute the sum of the fifth powers of the first n natural numbers. The article discusses the two approaches in detail and compares them with regards to efficiency and intuitiveness. Problem Statement The purpose of this problem is to compute the arithmetic sum of the first n natural numbers, all raised to their fifth power i.e. $\mathrm{1^5 + 2^5 + 3^5 + 4^5 + 5^5 + … + n^5}$  till the nth term. Examples Since n is a ... Read More

This article seeks a method for setting a given number's leftmost unset bit. The first unset bit after the most significant set bit is considered the leftmost unset bit. Problem Statement Given a number n, the task is to set the left most bit of the binary expansion of the number that is unset. All the other bits should be left unchanged. If all the bits of the original number are already set, return the number. Examples Input: 46 Output: 62 Explanation Binary Expansion of 46 = 101110. Left most unset bit is 101110. Upon setting the underlined ... Read More

A number is considered to be pernicious if the number is a positive integer and the number of set bits in its binary expansion are prime. The first pernicious number is 3, as 3 = (11)2. It can be seen that the number of set bits in the binary representation of 3 are 2, which is a prime number. The first 10 pernicious numbers are 3, 5, 6, 7, 9, 10, 11, 12, 13, 14. Interestingly, powers of 2 can never be pernicious since they always have only 1 set bit. 1 is not a prime number. On the other ... Read More

A number is considered to be an odious number if it has an odd number of 1s in its binary expansion. The first 10 odious numbers are 1, 2, 4, 7, 10, 11, 13, 14, 16, 19, 21. Interestingly, all powers of 2 are odious since they have only 1 set bit. The following article discusses 2 approaches in detail to find whether a number is an odious number or not. Problem Statement This problem aims to check whether the given number is an odious number i.e. it is a positive number with an odd number of set bits in ... Read More

In this problem, we need to find the total time required to complete all tasks according to the given condition. We can use the map data structure to solve the problem. We can keep tracking the last performed time for each task, and if the time interval is less than K, we can increment time units accordingly. Problem statement – We have given a string task containing alphabetical characters of length N. Each character represents a task, and we need one unit of time to perform the tasks. Also, the condition is that each task should be performed at ... Read More

We have given two strings and need to convert one string to another by click increments, and we can increment characters by either 1 or k in the single operation. To solve the problem, we need to make all characters of the first string the same as a second character by performing the cyclic increment operations. If the character at the same index in both strings is the same, we don’t need to perform any increment operation. Problem statement – We have given two strings named first and second containing the uppercase alphabetical characters. The length of both strings ... Read More

In this problem, we need to find the maximum length of the subsequence containing the single character by increasing the multiple characters by, at most, k times. We can use the sliding window approach to solve the problem. We can find the maximum length of any window to get the result after sorting the string. Problem statement – We have given string str containing lowercase alphabetical characters. Also, we have given the positive integer k. After performing the at most k increment operations with multiple characters of the given string, we need to find the maximum length of the ... Read More

In this problem, we need to generate a lexicographically smallest string using the first K characters of alphabets so that it doesn’t contain any repeated substring. We can generate a string so that all substrings of length 2 are unique. So, if all substrings of length 2 are unique, all substrings of length 3 or more are also unique. Problem statement – We have given a positive integer K. We need to generate a new string using the first K alphabets so that generated string can’t contain any repeated substring of length 2 or more and is lexicographically smallest. Sample ... Read More

In this problem, two players play a game by removing the string from their array, which is not already removed from the opponent's array. We need to decide the winner of the game. We can solve the problem using two different approaches. In the first approach, we can store the common strings with the set data structure. In the second approach, we can use a set to store already removed strings from both arrays. Problem statement – We have given two arrays called arr and brr. The size of the array is N and M, respectively. We need to decide ... Read More

In this problem, we have given a string suggesting the moving direction and starting coordinates. We need to find the revisited positions. We can use the set or map data structure to store the previously visited coordinates. We can say that position is revisited if we find any pair in the set or map. Problem statement – We have given a string str of length N containing the ‘L’, ‘R’, ‘U’, and ‘D’ characters. Also, we have given X and Y integers representing the starting position. We need to find the total number of coordinates revisited while following the path ... Read More