Scala Scripts Exercises.

diamond.scala

val width = 5
//width: Int = 5

val tTop = ( 0 until width/2 ) map ( n => 2 * n + 1 )
//tTop: scala.collection.immutable.IndexedSeq[Int] = Vector(1, 3)

val tBottom = tTop.reverse
//tBottom: scala.collection.immutable.IndexedSeq[Int] = Vector(3, 1)

val diamond = tTop union Seq(width) union tBottom
//diamond: scala.collection.immutable.IndexedSeq[Int] = Vector(1, 3, 5, 3, 1)

val offset = 3
//offset: Int = 3

val d = diamond map ( n => ( offset + (width - n)/2, n) )
//d: scala.collection.immutable.IndexedSeq[(Int, Int)] = Vector((5,1),
//(4,3), (3,5), (4,3), (5,1))

def printDiamond( s:Seq[(Int,Int)] ) = {
  s.foreach{ t =>
     ( 0 until t._1 ).foreach( _ => print(".") )
     ( 0 until t._2 ).foreach( _ => print("*") )
     print("\n")
  }
}
//printDiamond: (s: Seq[(Int, Int)])Unit

printDiamond(d)
//.....*
//....***
//...*****
//....***
//.....*