A function to flatten an array of arbitrarily nested arrays of integers into a flat array of integers.

flatten.kt

fun flattenedArray(array: Array<Array<Int>>): List<Int> {
    return array.flatten()
}

fun main(args: Array<String>) {
  println(flattenedArray(arrayOf(arrayOf(1), arrayOf(2, 3), arrayOf(4, 5), arrayOf(6, 7, 8)))
  //Output: [1, 2, 3, 4, 5, 6, 7, 8]        
}