Project Euler Problem 20

euler20.scala

object Main extends App {
	def factorial(n: BigInt, acc: BigInt = 1): BigInt =
		if (n == 0) acc else factorial(n - 1, acc * n)
	
	def sumOfDigits(a: BigInt) = {
		var n = a
		val digits = collection.mutable.ArrayBuffer[Int]()
		while (n > 0) {
			digits += (n % 10).toInt
			n = n / 10
		}
		digits.sum
	}
	val fact = factorial(BigInt(100))
	val sum = sumOfDigits(fact)
	
	println(fact + " " + sum)
}