fun main(args: Array<String>) {
   var num = intArrayOf(1, 3, 2, 6, 8)
   println(num.sum())
}

=> 20

fun main(args: Array<String>) {
   var num = intArrayOf(1, 3, 2, 6, 8)
   println(num.average())
}

=> 4.0

fun main(args: Array<String>) {
   var num = intArrayOf(1, 3, 2, 6, 8)
   println(num.max())
}

=> 8

fun main(args: Array<String>) {
   var num = intArrayOf(1, 3, 2, 6, 8)
   println(num.count())
}

=> 5