Learning Scala 1: swap array elements

Here posted my solution for the exercise 2 and 3 of Chapter 3 of page 39, in the book "Scala for the impatient".

Exercise 2.  Write a loop that swaps adjacent elements of an array of integers. For example,

Array(1, 2, 3, 4, 5)  becomes Array(2, 1, 4, 3, 5) .

Solution:

	val s = Array(1,2,3,4,5)
	for( i<-1 until (s.length, 2)) {
	val t = s(i-1)
	s(i-1) = s(i)
	s(i) = t
	}
	s
	//Array[Int] = Array(2, 1, 4, 3, 5)

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Exercise 3.  Repeat the preceding assignment, but produce a new array with the swapped

values. Use for /yield.

Solution:

	val s = Array(1,2,3,4,5)
	for ( i<-0 until s.length) yield {
	if ( i%2 == 1) s(i-1)
	else if(i == s.length-1) s(i)
	else s(i+1)
	}
	//scala.collection.immutable.IndexedSeq[Int] = Vector(2, 1, 4, 3, 5)

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Note: I realize you can not write java style for yield statement, like if ( i%2 ==0 ) yield s(i+1)