val list1 = List("This", "is", "an", "example");

val b = list1.aggregate(1)(_ * _.length(), _ * _)

val c = list1.aggregate(1)(_ * _.length(), _ + _)

def aggregate[B](z: ⇒ B)(seqop: (B, A) ⇒ B, combop: (B, B) ⇒ B): B

val l = List(1, 2, 3, 4)
l.aggregate(0)(_ + _, _ * _)