Is a random number the sum of 2 numbers in an array?

gistfile1.txt

function fn(num) {
	const validNumbers = []
	sortedNumbers.some((n) => {
		const comp = n > num
		if (!comp) {
			validNumbers.push(n)
		}
		return comp
	})
	
	let lower = 0
	let upper = validNumbers.length - 1
	
	while(lower <= upper) {
		const sum = validNumbers[lower] + validNumbers[upper]
		if (sum > num) {
			lower += 1
		} else if (sum < num) {
			upper -= 1
		} else {
			return true
		}
		
	}
	
	return false
}

function randomNumberGenerator() {
  return Math.ceil(Math.random() * 100)
}

const numbers = []

for(i = 0; i < 40; i++) {
  numbers.push(randomNumberGenerator())
}

const sortedNumbers = numbers.sort(function(a,b) {
  return a-b
})
console.log(sortedNumbers)

for(i = 0; i < 10; i++) {
  const number = randomNumberGenerator()
  console.log(number, fn(number))
}