find the largest product of 3 integers in an array

LargestProductOf3.scala

object LargestProductOf3
{
  def largestProductOf3(a: Array[Int]): Int = {
    var (max, max2, max3) = (a(0), a(0), a(0))
    var (min, min2) = (a(0), a(0))
    a.foreach(i => {
      if (i >= max) {
        max3 = max2
        max2 = max
        max = i
      } else if (i >= max2) {
        max3 = max2
        max2 = i
      } else if (i > max3) {
        max3 = i
      } else if (i <= min) {
        min2 = min
        min = i
      } else if (i < min2) {
        min2 = i
      }
    })
    return math.max(max * max2 * max3, min * min2 * max)
  }

  def largestProductOf3Naive(array: Array[Int]): Int = {
    var max = array(0)
    (0 until array.length - 2).foreach(i => {
      (i + 1 until array.length - 1).foreach(j => {
        (j + 1 until array.length).foreach(k => {
          max = math.max(max, array(i) * array(j) * array(k))
        })
      })
    })
    return max
  }

  def main(args: Array[String]): Unit = {
    val rand = scala.util.Random
    val array = new Array[Int](1000).map(_ => -1000 + rand.nextInt(2001))

    var elapsed = System.nanoTime()
    val fastResult = largestProductOf3(array)
    elapsed = (System.nanoTime() - elapsed)
    println(s"fast result $fastResult in ${elapsed / 1000000.0} ms")

    elapsed = System.nanoTime()
    val slowResult = largestProductOf3Naive(array)
    elapsed = (System.nanoTime() - elapsed)
    println(s"slow result $slowResult in ${elapsed / 1000000.0} ms")
  }
}