Roman Numeral Sort

RomanNumeralSort.kt

fun main() {
    val inputString =
        "I XV XIII XXX MM CLIV CM LXIX DX III XIX XVI CMXLIV M V IV CMLXIX MX CMX VIII DI XXIX XCIX MMMMMMMMMMCM"

    val numberList = getNumberList(inputString)

    numberList.sort()

    for (i in numberList) {
        printRomanNumeral(i)
    }
}

private fun getNumberList(inputString: String): MutableList<Int> {
    val numberList = mutableListOf<Int>()
    var acc = 0
    var lastValue = 0
    
    for (i in inputString.length - 1 downTo 0) {
        val symbol = inputString[i]

        if (symbol == ' ') {
            numberList.add(acc)
            acc = 0
            lastValue = 0
            continue
        }

        val number = when (symbol) {
            'I' -> 1
            'V' -> 5
            'X' -> 10
            'L' -> 50
            'C' -> 100
            'D' -> 500
            'M' -> 1000
            else -> 0
        }

        //subtract number if of the format IV, IX, XL, LC, CD, CM
        acc += when {
            (number == 1 && (lastValue == 5 || lastValue == 10)) ||
                    (number == 10 && (lastValue == 50 || lastValue == 100)) ||
                    (number == 100 && (lastValue == 500 || lastValue == 1000)) -> -number
            else -> number
        }

        if (i != 0) lastValue = number
        else numberList.add(acc)
    }

    return numberList
}

fun printRomanNumeral(i: Int) {
    var x = i
    var powTen = 0
    var string = ""

    while (x > 0) {
        //fix for very large numbers
        if (powTen == 3) {
            string = getRoman(x, powTen) + string
            break
        }

        val digit = x.rem(10)
        if (digit != 0) string = getRoman(digit, powTen) + string

        x /= 10
        powTen++
    }

    print("$string ")
}

fun getRoman(digit: Int, powTen: Int): String {
    when (powTen) {
        0 -> return when (digit) {
            in 1..3 -> "I".repeat(digit)
            4 -> "IV"
            5 -> "V"
            in 6..8 -> "V" + "I".repeat(digit - 5)
            9 -> "IX"
            else -> ""
        }
        1 -> return when (digit) {
            in 1..3 -> "X".repeat(digit)
            4 -> "XL"
            5 -> "L"
            in 6..8 -> "L" + "X".repeat(digit - 5)
            9 -> "XC"
            else -> ""
        }
        2 -> return when (digit) {
            in 1..3 -> "C".repeat(digit)
            4 -> "CD"
            5 -> "D"
            in 6..8 -> "D" + "C".repeat(digit - 5)
            9 -> "CM"
            else -> ""
        }
        else -> return "M".repeat(digit)
    }
}