June 2018 Update

Task/Number-names/AWK/number-names.awk

@@ -20,6 +20,7 @@ function numtowords(n,  minus,str) {
       str = intowords(n)
     }
     gsub(/  /," ",str)
+    gsub(/ $/,"",str)
     return(minus str)
 }
 function intowords(n) {

Task/Number-names/Go/number-names.go

@@ -3,52 +3,56 @@ package main
 import "fmt"
 
 func main() {
-    for _, n := range []int64{12, 1048576, 9e18} {
-        fmt.Println(say(n))
-    }
+	for _, n := range []int64{12, 1048576, 9e18, -2, 0} {
+		fmt.Println(say(n))
+	}
 }
 
-var small = []string{"", "one", "two", "three", "four", "five", "six",
-    "seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen",
-    "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"}
-var tens = []string{"ones", "ten", "twenty", "thirty", "forty",
-    "fifty", "sixty", "seventy", "eighty", "ninety"}
-var illions = []string{"thousand", "million", "billion",
-    "trillion", "quadrillion", "quintillion"}
+var small = [...]string{"zero", "one", "two", "three", "four", "five", "six",
+	"seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen",
+	"fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"}
+var tens = [...]string{"", "", "twenty", "thirty", "forty",
+	"fifty", "sixty", "seventy", "eighty", "ninety"}
+var illions = [...]string{"", " thousand", " million", " billion",
+	" trillion", " quadrillion", " quintillion"}
 
 func say(n int64) string {
-    switch {
-    case n < 1:
-    case n < 20:
-        return small[n]
-    case n < 100:
-        t := tens[n/10]
-        s := n % 10
-        if s > 0 {
-            t += " " + small[s]
-        }
-        return t
-    case n < 1000:
-        h := small[n/100] + " hundred"
-        s := n % 100
-        if s > 0 {
-            h += " " + say(s)
-        }
-        return h
-    default:
-        sx := say(n % 1000)
-        for i := 0; n >= 1000; i++ {
-            n /= 1000
-            p := n % 1000
-            if p > 0 {
-                ix := say(p) + " " + illions[i]
-                if sx > "" {
-                    ix += " " + sx
-                }
-                sx = ix
-            }
-        }
-        return sx
-    }
-    return ""
+	var t string
+	if n < 0 {
+		t = "negative "
+		// Note, for math.MinInt64 this leaves n negative.
+		n = -n
+	}
+	switch {
+	case n < 20:
+		t += small[n]
+	case n < 100:
+		t += tens[n/10]
+		s := n % 10
+		if s > 0 {
+			t += "-" + small[s]
+		}
+	case n < 1000:
+		t += small[n/100] + " hundred"
+		s := n % 100
+		if s > 0 {
+			t += " " + say(s)
+		}
+	default:
+		// work right-to-left
+		sx := ""
+		for i := 0; n > 0; i++ {
+			p := n % 1000
+			n /= 1000
+			if p > 0 {
+				ix := say(p) + illions[i]
+				if sx != "" {
+					ix += " " + sx
+				}
+				sx = ix
+			}
+		}
+		t += sx
+	}
+	return t
 }

Task/Number-names/Java/number-names-1.java

@@ -1,46 +1,60 @@
-public class Int2Words {
-    static String[] small = {"one", "two", "three", "four", "five", "six",
-        "seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen", "fourteen",
-        "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"};
-    static String[] tens = {"twenty", "thirty", "forty", "fifty", "sixty", "seventy", "eighty",
-        "ninety"};
-    static String[] big = {"thousand", "million", "billion", "trillion"};
+public enum IntToWords {
+    ;
+
+    private static final String[] small = {
+            "", "one", "two", "three", "four",
+            "five", "six", "seven", "eight", "nine",
+            "ten", "eleven", "twelve", "thirteen", "fourteen",
+            "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"};
+    private static final String[] tens = {
+            "", "", "twenty", "thirty", "forty",
+            "fifty", "sixty", "seventy", "eighty", "ninety"};
+    private static final String[] big = {
+            "", "thousand", "million", "billion", "trillion",
+            "quadrillion", "quintillion"};
 
     public static void main(String[] args) {
-        System.out.println(int2Text(900000001));
-        System.out.println(int2Text(1234567890));
-        System.out.println(int2Text(-987654321));
         System.out.println(int2Text(0));
+        System.out.println(int2Text(10));
+        System.out.println(int2Text(30));
+        System.out.println(int2Text(47));
+        System.out.println(int2Text(100));
+        System.out.println(int2Text(999));
+        System.out.println(int2Text(1000));
+        System.out.println(int2Text(9999));
+        System.out.println(int2Text(123_456));
+        System.out.println(int2Text(900_000_001));
+        System.out.println(int2Text(1_234_567_890));
+        System.out.println(int2Text(-987_654_321));
+        System.out.println(int2Text(Long.MAX_VALUE));
+        System.out.println(int2Text(Long.MIN_VALUE));
     }
 
     public static String int2Text(long number) {
-        long num = 0;
-        String outP = "";
-        int unit = 0;
-        long tmpLng1 = 0;
+        StringBuilder sb = new StringBuilder();
 
         if (number == 0) {
             return "zero";
         }
 
-        num = Math.abs(number);
+        long num = -Math.abs(number);
 
-        for (;;) {
-            tmpLng1 = num % 100;
-            if (tmpLng1 >= 1 && tmpLng1 <= 19) {
-                outP = small[(int) tmpLng1 - 1] + " " + outP;
-            } else if (tmpLng1 >= 20 && tmpLng1 <= 99) {
-                if (tmpLng1 % 10 == 0) {
-                    outP = tens[(int) (tmpLng1 / 10) - 2] + " " + outP;
+        int unit = 1;
+        while (true) {
+            int rem100 = (int) -(num % 100);
+            if (rem100 >= 20) {
+                if (rem100 % 10 == 0) {
+                    sb.insert(0, tens[rem100 / 10] + " ");
                 } else {
-                    outP = tens[(int) (tmpLng1 / 10) - 2] + "-"
-                            + small[(int) (tmpLng1 % 10) - 1] + " " + outP;
+                    sb.insert(0, tens[rem100 / 10] + "-" + small[rem100 % 10] + " ");
                 }
+            } else if (rem100 != 0) {
+                sb.insert(0, small[rem100] + " ");
             }
 
-            tmpLng1 = (num % 1000) / 100;
-            if (tmpLng1 != 0) {
-                outP = small[(int) tmpLng1 - 1] + " hundred " + outP;
+            int hundreds = (int) -(num % 1000) / 100;
+            if (hundreds != 0) {
+                sb.insert(0, small[hundreds] + " hundred ");
             }
 
             num /= 1000;
@@ -48,17 +62,17 @@ public class Int2Words {
                 break;
             }
 
-            tmpLng1 = num % 1000;
-            if (tmpLng1 != 0) {
-                outP = big[unit] + " " + outP;
+            int rem1000 = (int) -(num % 1000);
+            if (rem1000 != 0) {
+                sb.insert(0, big[unit] + " ");
             }
             unit++;
         }
 
         if (number < 0) {
-            outP = "negative " + outP;
+            sb.insert(0, "negative ");
         }
 
-        return outP.trim();
+        return sb.toString().trim();
     }
 }

Task/Number-names/JavaScript/number-names.js

@@ -0,0 +1,44 @@
+const divMod = y => x => [Math.floor(y/x), y % x];
+
+const sayNumber = value => {
+  let name = '';
+  let quotient, remainder;
+  const dm = divMod(value);
+  const units = ['zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven',
+    'eight', 'nine', 'ten', 'eleven', 'twelve', 'thirteen', 'fourteen',
+    'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen'];
+  const tens = ['', '', 'twenty', 'thirty', 'forty', 'fifty', 'sixty',
+    'seventy', 'eighty', 'ninety'];
+  const big = [...['', 'thousand'], ...['m', 'b', 'tr', 'quadr', 'quint',
+    'sext', 'sept', 'oct', 'non', 'dec'].map(e => `${e}illion`)];
+
+  if (value < 0) {
+    name = `negative ${sayNumber(-value)}`
+  } else if (value < 20) {
+    name = units[value]
+  } else if (value < 100) {
+    [quotient, remainder] = dm(10);
+    name = `${tens[quotient]} ${units[remainder]}`.replace(' zero', '');
+  } else if (value < 1000) {
+    [quotient, remainder] = dm(100);
+    name = `${sayNumber(quotient)} hundred and ${sayNumber(remainder)}`
+      .replace(' and zero', '')
+  } else {
+    const chunks = [];
+    const text = [];
+    while (value !== 0) {
+      [value, remainder] = divMod(value)(1000);
+      chunks.push(remainder);
+    }
+    chunks.forEach((e,i) => {
+      if (e > 0) {
+        text.push(`${sayNumber(e)}${i === 0 ? '' : ' ' + big[i]}`);
+        if (i === 0 && e < 100) {
+          text.push('and');
+        }
+      }
+    });
+    name = text.reverse().join(', ').replace(', and,', ' and');
+  }
+  return name;
+};