HackerRank: List Length

ListLength.scala

package list.length

object Main {
	def f(arr: List[Int]): Int = arr match {
		case x :: xs => 1 + f(xs)
		case _ => 0
	}
	
	def main(args: Array[String]) {
		val len = f(List(1, 2, 3));
		println(len);
	}
}