Scala solution to http://blog.jazzychad.net/2012/08/01/array-iteration-problem.html (while loop, in-place)

gistfile1.scala

def add1(arr: Array[Int], value: Int, n: Int): Array[Int] = {
	n match {
		case 0 => loop(arr, value, 0, 1, {_ < arr.length}, arr.length)
		case m if m > 0 => loop(arr, value, 0, 1, {_ < arr.length}, m)
		case m if m < 0 => loop(arr, value, arr.length - 1, -1, {_ > 0}, -m)
	}
	arr
}

private def loop(arr: Array[Int], value: Int, startIndex: Int, step: Int, continueCond: Int => Boolean, maxIncr: Int) {
	var i = startIndex
	var inc = 0
	while (continueCond(i) && inc < maxIncr) {
		if (arr(i) == value) {
			arr(i) += 1	
			inc += 1
		}
		i += step
	}
}

val arr1 = Array(1,4,1,5,1)
val arr2 = Array(1,4,1,5,1)
val arr3 = Array(1,4,1,5,1)

add1(arr1, 1, 0) // -> Array(2, 4, 2, 5, 2)

add1(arr2, 1, 2) // -> Array(2, 4, 2, 5, 1)

add1(arr3, 1, -2) // -> Array(1, 4, 2, 5, 2)