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The power set of a set S is the set of all of the subsets of S, including the empty set and S itself. The power set of set S is denoted as P(S).For exampleIf S = {x, y, z}, the subsets are −{ {}, {x}, {y}, {z}, {x, y}, {x, z}, {y, z}, {x, y, z} }We are required to write a JavaScript function that takes in an array as the only argument. The function should find and return the power set for the input array.ExampleFollowing is the code −const set ... Read More
RadianThe radian is the unit for measuring angles and is the standard unit of angular measure used in many areas of mathematics.We are required to write a JavaScript function that takes in a number that represents some degree and returns its corresponding radian.ExampleFollowing is the code −const deg = 180; const degreeToRadian = (degree) => { const factor = (Math.PI / 180); const rad = degree / factor; return rad; }; console.log(degreeToRadian(deg));OutputFollowing is the output on console −10313.240312354817
Suppose we have the following problem −There are n stairs, a person standing at the bottom wants to reach the top. The person can climb either 1 or 2 stairs at a time. We are required to count the number of ways, the person can reach the top.We are required to write a JavaScript function that takes in a number n that denotes the number of stairs. The function should count and return the number of ways in which the stairs can be climbed.ExampleFollowing is the code −const recursiveStaircase = (num = 10) => { if (num
Block SearchJust like Binary Search, Block Search is also a searching algorithm for sorted arrays. The basic idea is to check fewer elements (than linear search) by jumping ahead by fixed steps or skipping some elements in place of searching all elements.For exampleSuppose we have an array arr of length n and block (to be jumped) of size m. Then we search at the indexes arr[0], arr[m], arr[2 * m], ..., arr[k * m] and so on.Once we find the interval arr[k * m] < x < arr[(k+1) * m], we perform a linear search operation from the index k ... Read More
Hamming DistanceThe Hamming distance between two strings of equal length is the number of positions at which the corresponding symbols are different.For example, consider the following strings −const str1 = 'delhi'; const str2 = 'delph';The Hamming Distance of these strings is 2 because the fourth and the fifth characters of the strings are different. And obviously in order to calculate the Hamming Distance we need to have two strings of equal lengths.Therefore, we are required to write a JavaScript function that takes in two strings, let’s say str1 and str2, and returns their hamming distance.ExampleFollowing is the code −const str1 ... Read More
The least common multiple, (LCM) of two integers a and b, is the smallest positive integer that is divisible by both a and b.For example −LCM of 4 and 6 is 12 because 12 is the smallest number that is exactly divisible by both 4 and 6.We are required to write a JavaScript function that takes in two numbers, computes and returns the LCM of those numbers.ExampleFollowing is the code −const num1 = 4; const num2 = 6; const findLCM = (num1, num2) => { let hcf; for (let i = 1; i
Suppose we are given a set of candidate numbers (without duplicates) and a target number (target).We are required to write a function that finds all unique combinations in candidates where the candidate numbers sum to the target.The same repeated number may be chosen from candidates an unlimited number of times.Note −All numbers (including target) will be positive integers.The solution set must not contain duplicate combinations.For example −If the inputs are −candidates = [2, 3, 6, 7], target = 7, The solution to this can be −[ [7], [2, 2, 3] ];Since the problem is to get all the ... Read More
Suppose we are given an input string str and a pattern p, we are required to implement regular expression matching with support for. and *.The functions of these symbols should be −. --> Matches any single character.* --> Matches zero or more of the preceding elements.The matching should cover the entire input string (not partial).Notestr could be empty and contains only lowercase letters a-z.p could be empty and contains only lowercase letters a-z, and characters like. or *.For example −If the input is −const str = 'aa'; const p = 'a';Then the output should be false because a does not ... Read More
We are required to write a JavaScript function that takes in a number and determines whether or not it is a power of two.For example −f(23) = false f(16) = true f(1) = true f(1024) = trueApproach −Powers of two in binary form always have just one bit. Like this −1: 0001 2: 0010 4: 0100 8: 1000Therefore, after checking that the number is greater than zero, we can use a bitwise hack to test that one and only one bit is set. The same is shown below −num & (num - 1)ExampleFollowing is the code −const num1 = 256; ... Read More
In mathematics, Euclid's algorithm, is a method for computing the greatest common divisor (GCD) of two numbers, the largest number that divides both of them without leaving a remainder.The Euclidean algorithm is based on the principle that the greatest common divisor of two numbers does not change if the larger number is replaced by its difference with the smaller number.For example, 21 is the GCD of 252 and 105 (as 252 = 21 × 12 and 105 = 21 × 5), and the same number 21 is also the GCD of 105 and 252 − 105 = 147.Since this replacement ... Read More