Project Euler Problem 10

gistfile1.scala

/**
 * Project Euler Problem 10
 */
object P10 {

	def primes(limit:Int): List[Int] = {
		require(limit > 1)

		def go(primes:List[Int], search:List[Int]):List[Int] = {
			val prime = search.head
			if (prime * prime < limit)
				go(prime :: primes, search.tail.filterNot(_ % prime == 0))
			else
				primes.reverse ++ search 
		}
		go(Nil, (2 to limit).toList)
	}

	def answer():Long = primes(2000000).foldLeft(0l)(_ + _)
}