Data commit

Task/Number-names/Kotlin/number-names.kotlin

@@ -0,0 +1,73 @@
+// version 1.1.2
+
+val oneNames = listOf(
+        "", "one", "two", "three", "four",
+        "five", "six", "seven", "eight", "nine",
+        "ten", "eleven", "twelve", "thirteen", "fourteen",
+        "fifteen", "sixteen", "seventeen", "eighteen", "nineteen")
+val tenNames = listOf(
+        "", "", "twenty", "thirty", "forty",
+        "fifty", "sixty", "seventy", "eighty", "ninety")
+val thousandNames = listOf(
+        "", "thousand", "million", "billion", "trillion", "quadrillion",
+        "quintillion")
+
+fun numToText(n: Long, uk: Boolean = false): String {
+    if (n == 0L) return "zero"
+    val neg = n < 0L
+    val maxNeg = n == Long.MIN_VALUE
+    var nn = if (maxNeg) -(n + 1) else if (neg) -n else n
+    val digits3 = IntArray(7)
+    for (i in 0..6) {  // split number into groups of 3 digits from the right
+        digits3[i] = (nn % 1000).toInt()
+        nn /= 1000
+    }
+    if (maxNeg) digits3[0]++
+
+    fun threeDigitsToText(number: Int): String {
+        val sb = StringBuilder()
+        if (number == 0) return ""
+        val hundreds = number / 100
+        val remainder = number % 100
+        if (hundreds > 0) {
+            sb.append(oneNames[hundreds], " hundred")
+            if (remainder > 0) sb.append(if (uk) " and " else " ")
+        }
+        if (remainder > 0) {
+            val tens = remainder / 10
+            val units = remainder % 10
+            if (tens > 1) {
+                sb.append(tenNames[tens])
+                if (units > 0) sb.append("-", oneNames[units])
+            } else sb.append(oneNames[remainder])
+        }
+        return sb.toString()
+    }
+
+    val triplets = Array(7) { threeDigitsToText(digits3[it]) }
+    var text = triplets[0]
+    var andNeeded = uk && digits3[0] in 1..99
+    for (i in 1..6) {
+        if (digits3[i] > 0) {
+            var text2 = triplets[i] + " " + thousandNames[i]
+            if (text != "") {
+                text2 += if (andNeeded) " and " else ", "
+                andNeeded = false
+            } else andNeeded = uk && digits3[i] in 1..99
+            text = text2 + text
+        }
+    }
+    return (if (neg) "minus " else "") + text
+}
+
+fun main() {
+    val exampleNumbers = longArrayOf(
+            0, 1, 7, 10, 18, 22, 67, 99, 100, 105, 999, -1056, 1000005000,
+            2074000000, 1234000000745003L, Long.MIN_VALUE
+    )
+    println("Using US representation:")
+    for (i in exampleNumbers) println("${"%20d".format(i)} = ${numToText(i)}")
+    println()
+    println("Using UK representation:")
+    for (i in exampleNumbers) println("${"%20d".format(i)} = ${numToText(i, true)}")
+}