fun main() {
    println(generateListOfLists(2, 5, 0, 100, 4))
}

fun generateListOfLists(
    minSize: Int,
    maxSize: Int,
    minNumber: Int,
    maxNumber: Int,
    numberOfLists: Int
): List<List<Int>> {
    val sizes = generateDistinctSizes(minSize, maxSize, numberOfLists)
    return generateLists(sizes, minNumber, maxNumber, mutableListOf(), 0)
}

private fun generateDistinctSizes(
    minSize: Int,
    maxSize: Int,
    numberOfLists: Int
): List<Int> {
    val distinctRandomSizes = mutableSetOf<Int>()
    while (distinctRandomSizes.size < numberOfLists) {
        distinctRandomSizes.add((minSize..maxSize).random())
    }
    return distinctRandomSizes.toList()
}

tailrec fun generateLists(
    sizes: List<Int>,
    minNumber: Int,
    maxNumber: Int, acc: MutableList<List<Int>>, currentSizeIndex: Int
): List<List<Int>> {
    return if (currentSizeIndex == sizes.size) {
        acc
    } else {
        val size = sizes[currentSizeIndex]
        acc.add(generateRandomSortedList(size, minNumber, maxNumber, chooseComparator(currentSizeIndex)))
        generateLists(sizes, minNumber, maxNumber, acc, currentSizeIndex + 1)
    }
}

fun generateRandomSortedList(
    size: Int,
    minNumber: Int,
    maxNumber: Int,
    comparator: Comparator<Int>
): List<Int> =
    List(size) { (minNumber..maxNumber).random() }
        .sortedWith(comparator)


fun chooseComparator(i: Int): Comparator<Int> =
    if (i % 2 == 0)
        ascending
    else
        descending

object ascending : Comparator<Int> {
    override fun compare(x: Int, y: Int): Int = x - y
}

object descending : Comparator<Int> {
    override fun compare(x: Int, y: Int): Int = y - x
}