Project Euler Problem 7

gistfile1.scala

/**
 * Project Euler Problem 7
 */
object P7 {
  def from(n:Long):Stream[Long] = n #:: from(n + 1)

	def primes(): Stream[Long] = {

		import scala.collection.mutable.ListBuffer

		def f(ps: ListBuffer[Long], l: Stream[Long]): Stream[Long] = {
	    	val head = l.find(x => !ps.exists(x % _ ==0)).get
     		head #:: f(ps += head, from(head + 1))
		}
		f(new ListBuffer[Long], from(2))
	}

  	def answer():Long = primes.take(10001).last
}