Moore's Voting Algorithm - Boyer-Moore Majority Voting Algorithm #1750

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		* [NumberOfLocalMaximumPoints](Data-Structures/Array/NumberOfLocalMaximumPoints.js)
		* [QuickSelect](Data-Structures/Array/QuickSelect.js)
		* [Reverse](Data-Structures/Array/Reverse.js)
	* [MooreVotingAlgorithm](Data-Structures/Array/MooreVotingAlgorithm.js)
		* Graph
		* [Graph](Data-Structures/Graph/Graph.js)
		* [Graph2](Data-Structures/Graph/Graph2.js)
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29 changes: 29 additions & 0 deletions Data-Structures/Array/MooreVotingAlgorithm.js

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	/**
	* Moore Voting Algorithm to find the majority element in an array
	* Majority element is the one that appears more than n/2 times
	* geeksforgeeks: https://www.geeksforgeeks.org/boyer-moore-majority-voting-algorithm/
	* @param {Array} arr array of integers
	* @returns {Number} majority element or null if no majority exists
	*/
	const MooreVotingAlgorithm = (arr) => {
	let candidate = null
	let count = 0

	// Phase 1: Find the candidate for majority element
	for (let num of arr) {
	if (count === 0) {
	candidate = num
	}
	count += num === candidate ? 1 : -1
	}

	// Phase 2: Verify if the candidate is actually the majority element
	count = 0
	for (let num of arr) {
	if (num === candidate) {
	count++
	}
	}
	return count > arr.length / 2 ? candidate : null
	}
	export { MooreVotingAlgorithm }

11 changes: 11 additions & 0 deletions Data-Structures/Array/test/MooreVotingAlgorithm.test.js

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	import { MooreVotingAlgorithm } from '../MooreVotingAlgorithm'
	describe('Moore Voting Algorithm', () => {
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	it.each([
	[[1, 1, 2, 1, 3, 1, 1], 1], // Majority element 1
	[[2, 2, 2, 2, 5, 5, 5, 2], 2], // Majority element 2
	[[3], 3], // Single element, it's the majority
	[[1, 2, 3, 4, 5, 6, 7], null] // No majority element in the array
	])('returns %j when given %j', (array, expected) => {
	expect(MooreVotingAlgorithm(array)).toEqual(expected)
	})
	})

17 changes: 10 additions & 7 deletions Maths/MobiusFunction.js

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		* @param {Integer} number
		* @returns {Integer}
		*/

		import { PrimeFactors } from './PrimeFactors.js'

		export const mobiusFunction = (number) => {
	const primeFactorsArray = PrimeFactors(number)
		if (number <= 0) {
		throw new Error('Number must be greater than zero.')
		}
	return primeFactorsArray.length !== new Set(primeFactorsArray).size
	? 0
	: primeFactorsArray.length % 2 === 0
	? 1
	: -1

	const primeFactorsArray = PrimeFactors(number)
	const uniquePrimeFactors = new Set(primeFactorsArray)

	// If there are duplicate factors, it means number is not square-free.
	if (primeFactorsArray.length !== uniquePrimeFactors.size) {
	return 0
	}
	return uniquePrimeFactors.size % 2 === 0 ? 1 : -1
		}

6 changes: 4 additions & 2 deletions package-lock.json

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6 changes: 3 additions & 3 deletions package.json

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