nikoo28

Question: If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below ‘N’ Input: N = 100 Output: 2318 The most naive approach to solve this problem will be Iterate over each number till N If the number is divisible by 3 or 5, add it to the sum Print the sum This approach can work well to numbers…

Question: Given a string, identify the index of character to be removed to change the string into a palindrome. If the string cannot be converted to palindrome or is already a palindrome just return -1. Input: abckdeedcbaOutput: 3 (0 based indexing) To start off with the problem, we must first understand that there can be two possible ways to make the string a palindrome. If the given string is “bcbc”. If we remove the first ‘b’, the string becomes “cbc” which is a palindrome. If we remove the last ‘c’,…

Let us try to simplify the problem as much as we can. We are given with some of the terms. Weights:- According to the problem each character in the English alphabet has been assigned a weight. ‘a’ has been given a weight of 1, ‘b’ has a weight of 2, and so on. The weight of ‘z’ is 26. All the letters are assumed to be lowercase for simplicity. Weight of a string:- This is defined as the sum of all the characters in the string. Example if a string…

Question: Given a string, identify if it is a pangram. Input: The quick brown fox jumps over the lazy little dog.Output: pangram To start with the problem statement we must first understand what is a pangram. A pangram is a string that contains all the characters in the English alphabet at-least once. This means that the string ‘the quick brown fox jumps over the lazy little dog’ will cover each of the letter from ‘a-z’. So how to identify if a string is a pangram?You need to keep a check…

A string is said to be valid when it has only distinct characters and none of them repeat simultaneously. For example, if string ‘s two distinct characters are x and y, then valid examples could be xyxyx or yxyxy but not xxyy or xyyx.Question: Given a sample string, we need to determine what is the maximum length of valid string that can be made by deleting any of the characters.Input: beabeefeabOutput: 5 Explanation: Let us try to understand the output for the sample test case.If we delete e and f,…

Question: Given a string, find the next lexicographic permutation. Input: abcOutput: acb First of all let us try to understand what do you mean by next lexicographic string. To get a hold of the concept try to remember an English dictionary and how words are arranged in it. We start with the letter ‘a’, write all the words and then move to letter ‘b’ all the way to letter ‘z’. This is called as a lexicographic order.This is possible when we have all the letters in English alphabet available to…

Question: Given an unsorted array of integers and a number ‘k’. Return the kth largest element in the array.Input: arr = {3,2,1,5,6,4}, k = 2Output: 5 Given an unsorted array of integers, you need to determine the kth largest element. By taking a first glance at the problem we can be sure of one thing. If the array is already sorted in ascending order, we can simply return the element at arr[size – k]. This would give us the kth largest element. This is because the 2nd largest element is…

Question: Given an integer N, convert it into a string of words. Input: N = 345 Output: three hundred forty five This is one of the most common problems that we come across in out daily lives. We need to input a number from the user and print it in words. First, we perform a number of checks on the input string. If it is in any way invalid, the result is the empty string (“”). Next, we take note of whether or not the string begins with a ‘-‘.…

In this post, I would try to implement the following string-related algorithm questions. I would like to implement these using Java and try to make additional comments which I think that are useful for understanding the implementations of some type of data structures in Java programming language. Non Repeated Characters in String : Return the unique characters in a given letter. Anagram Strings : Given two strings, check if they’re anagrams or not. Two strings are anagrams if they are written using the same exact letters, ignoring space, punctuation and…

Question: Given an integer N, find the prime numbers in that range from 1 to N. Input: N = 25Output: 2, 3, 5, 7, 11, 13, 17, 19, 23 We discussed the basic approaches to find the first N prime numbers in these posts Find the first N prime numbers (Method 1) Find the first N prime numbers (Method 2) It is advised that you go through the above posts to get a basic understanding of the approach that we have used to determine the prime numbers. Now lets analyze…