Two Number Sum algorithm (Solution using two methods)

numSumAlgo.js

// Two Number sum algorithm challenge
// Solution using the algebraic method
 const twoNumberSum = (array, targetSum) => {
	const hashTable = {}
	for (let value of array) {
		let yValue = targetSum - value;
		if (hashTable[yValue]) {
			return [yValue, value]
		}
		else {
			hashTable[value] = true
		}
	}
	return []
}
let array = [-1, 4, 5, 9, 2, 19, 14, 57, 102, 73];
let targetSum = 87;
twoNumberSum(array, targetSum)

numSumAlgo2.js

// sorting algorithm method
const twoNumberSum = (array, targetSum) => {
	let sortedArray = array.sort((a, b) => a - b);
	let countFwd = 0;
	let countBwd = 1;
	let firstPointer = sortedArray[countFwd]
	let lastPointer = sortedArray[sortedArray.length - countBwd]
	
	for(let i = 0; i < sortedArray.length; i++) {
		let sum = firstPointer + lastPointer;
		if(targetSum > sum) {
			firstPointer = sortedArray[countFwd++]
		}
		else if(targetSum < sum) {
			lastPointer = sortedArray[sortedArray.length - countBwd++]
		}
		else{
			return [firstPointer, lastPointer]
		}
	}
	return []
}
let array = [-1, 4, 5, 9, 2, 19, 14, 57, 102, 73];
let targetSum = 87;
twoNumberSum(array, targetSum)

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