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Commit a62a46e

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Resolve duplicate entries for sieve of eratosthenes (#1770)
* remove intarr test * Remove main file oops * FIXES: #1666 , remove references to SieveOfEratosthenesIntArray * Finally fix the requirements, passes vitest * Updated Documentation in README.md * FIXES: #1666 and conform to alg comment standards --------- Co-authored-by: SpiderMath <SpiderMath@users.noreply.github.com>
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‎DIRECTORY.md

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* [RowEchelon](Maths/RowEchelon.js)
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* [ShorsAlgorithm](Maths/ShorsAlgorithm.js)
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* [SieveOfEratosthenes](Maths/SieveOfEratosthenes.js)
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* [SieveOfEratosthenesIntArray](Maths/SieveOfEratosthenesIntArray.js)
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* [Signum](Maths/Signum.js)
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* [SimpsonIntegration](Maths/SimpsonIntegration.js)
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* [Softmax](Maths/Softmax.js)

‎Maths/SieveOfEratosthenes.js

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const sieveOfEratosthenes = (n) => {
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/*
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* Calculates prime numbers till a number n
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* :param n: Number up to which to calculate primes
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* :return: A boolean list containing only primes
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*/
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const primes = new Array(n + 1)
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primes.fill(true) // set all as true initially
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primes[0] = primes[1] = false // Handling case for 0 and 1
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const sqrtn = Math.ceil(Math.sqrt(n))
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for (let i = 2; i <= sqrtn; i++) {
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if (primes[i]) {
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for (let j = i * i; j <= n; j += i) {
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/*
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Optimization.
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Let j start from i * i, not 2 * i, because smaller multiples of i have been marked false.
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/**
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* @function sieveOfEratosthenes
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* @description Function to get all the prime numbers below a given number using sieve of eratosthenes algorithm
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* @param {Number} max The limit below which all the primes are required to be
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* @returns {Number[]} An array of all the prime numbers below max
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* @see [Sieve of Eratosthenes](https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes)
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* @example
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* sieveOfEratosthenes(1) // ====> []
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* @example
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* sieveOfEratosthenes(20) // ====> [2, 3, 5, 7, 11, 13, 17, 19]
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*
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*/
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function sieveOfEratosthenes(max) {
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const sieve = []
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const primes = []
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For example, let i = 4.
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We do not have to check from 8(4 * 2) to 12(4 * 3)
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because they have been already marked false when i=2 and i=3.
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*/
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primes[j] = false
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for (let i = 2; i <= max; ++i) {
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if (!sieve[i]) {
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// If i has not been marked then it is prime
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primes.push(i)
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for (let j = i << 1; j <= max; j += i) {
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// Mark all multiples of i as non-prime
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sieve[j] = true
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}
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}
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}

‎Maths/SieveOfEratosthenesIntArray.js

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‎Maths/test/SieveOfEratosthenes.test.js

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import { sieveOfEratosthenes } from '../SieveOfEratosthenes'
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import { PrimeCheck } from '../PrimeCheck'
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describe('should return an array of prime booleans', () => {
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it('should have each element in the array as a prime boolean', () => {
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const n = 30
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const primes = sieveOfEratosthenes(n)
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primes.forEach((primeBool, index) => {
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if (primeBool) {
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expect(PrimeCheck(index)).toBeTruthy()
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}
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})
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describe('sieveOfEratosthenes', () => {
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test('returns an empty array for max < 2', () => {
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expect(sieveOfEratosthenes(1)).toEqual([])
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})
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test('returns [2] for max = 2', () => {
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expect(sieveOfEratosthenes(2)).toEqual([2])
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})
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test('returns [2, 3] for max = 3', () => {
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expect(sieveOfEratosthenes(3)).toEqual([2, 3])
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})
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test('returns [2, 3, 5, 7] for max = 10', () => {
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expect(sieveOfEratosthenes(10)).toEqual([2, 3, 5, 7])
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})
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test('returns [2, 3, 5, 7, 11, 13, 17, 19] for max = 20', () => {
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expect(sieveOfEratosthenes(20)).toEqual([2, 3, 5, 7, 11, 13, 17, 19])
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})
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test('returns [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] for max = 30', () => {
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expect(sieveOfEratosthenes(30)).toEqual([
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2, 3, 5, 7, 11, 13, 17, 19, 23, 29
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])
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})
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})

‎Maths/test/SieveOfEratosthenesIntArray.test.js

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‎Project-Euler/Problem035.js

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*
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* @author ddaniel27
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*/
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import { sieveOfEratosthenes } from '../Maths/SieveOfEratosthenesIntArray'
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import { sieveOfEratosthenes } from '../Maths/SieveOfEratosthenes'
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function problem35(n) {
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if (n < 2) {

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