Print number in words

Question

Hi, I am trying code to print a three digit number in words. But this isn't working if first two digits from right are between 11 & 19 (both including).

Any help?

package com;

import java.util.Stack;

public class TestMain {
public static void main(String[] args) {

Integer i=512;
int temp =i;int pos=1;
Stack<String> stack=new Stack<String>();
while(temp>0){

 int rem=temp%10;
 temp=temp/10;
 if(rem!=0){stack.push(getString(rem, pos));}
 pos*=10;
}
do{
 System.out.print(stack.pop()+" ");
}while(!stack.isEmpty());



}
static String getString(int i,int position){
 String str=null;

 if(position==10){
  i*=position;
 }

 switch(i){
 case 1:
  str= "One";break;

 case 2:
  str= "two";break;
 case 3:
  str= "three";break;
 case 4:
  str= "four";break;
 case 5:
  str= "five";break;
 case 6:
  str= "six";break;
 case 7:
  str= "seven";break;
 case 8:
  str= "eight";break;
 case 9:
  str= "nine";break;
 case 10:
  str= "Ten";break;
 case 11:
  str= "Eleven";break;
 case 12:
  str= "Twelve";break;
 case 13:
  str= "thirteen";break;
 case 14:
  str= "fourteen";break;
 case 15:
  str= "fifteen";break;
 case 16:
  str= "sixteen";break;
 case 17:
  str= "seventeen";break;
 case 18:
  str= "eighteen";break;
 case 19:
  str= "Nineteen"; break;
 case 20:
  str= "twenty";break;
 case 30:
  str= "Thirty";break;
 case 40:
  str= "forty";break;
 case 50:
  str= "Fifty";break;
 case 60:
  str= "sixty";break;
 case 70:
  str= "Seventy";break;
 case 80:
  str= "Eighty"; break;
 case 90:
  str= "Ninety";break;
 case 100:
  str= "Hundred";
  break;
 }
 if(position>=100){
 str=str+ " "+getString(position, 0);
 }
 return str;
}

}

Answer 1

• You have to treat zero specially.
• You are using modulo 10 in the test main program, so you don't see 11-20 in the called function. Actually, it is not clear that you see 20, 30, 40, etc either.
• Your capitalization is inconsistent; good programmers are paranoid about consistency.

Answer 2

It's been done and posted so you can benefit:

http://www.rgagnon.com/javadetails/java-0426.html

Answer 3

For a three-digit (non-negative) number, you just need to divide it into sections and remember that numbers less than 20 are special (in any block of a hundred). Pseudocode (well, Python, actually but close enough to pseudocode):

nums1 = ["","one","two","three","four","five","six","seven",
         "eight","nine","ten","eleven","twelve","thirteen",
         "fourteen","fifteen","sixteen","seventeen","eighteen",
         "nineteen"]
nums2 = ["","","twenty","thirty","forty","fifty","sixty",
         "seventy","eighty","ninety"]

def speak (n):
    if n == 0:
        return "zero"

    hundreds = int (n / 100)
    tens = int ((n % 100) / 10)
    ones = n % 10

    if hundreds > 0:
        retstr = nums1[hundreds] + " hundred"
        if tens != 0 or ones != 0:
            retstr = retstr + " and "
    else:
        retstr = ""

    if tens != 0 or ones != 0:
        if tens < 2:
            retstr = retstr + nums1[tens*10+ones]
        else:
            retstr = retstr + nums2[tens]
            if ones != 0:
                retstr = retstr + " " + nums1[ones]
    return retstr

for i in range (0, 1000):
    print i, speak (i)

produces:

0 zero
1 one
2 two
3 three
4 four
5 five
6 six
7 seven
8 eight
9 nine
10 ten
11 eleven
12 twelve
13 thirteen
14 fourteen
15 fifteen
16 sixteen
17 seventeen
: : : : : 
993 nine hundred and ninety three
994 nine hundred and ninety four
995 nine hundred and ninety five
996 nine hundred and ninety six
997 nine hundred and ninety seven
998 nine hundred and ninety eight
999 nine hundred and ninety nine

Answer 4

Here is the code in Java:

private static String[] DIGIT_WORDS = {
    "zero", "one", "two", "three", "four",
    "five", "six", "seven", "eight", "nine" };
private static String[] TENS_WORDS = {
    "ten", "twenty", "thirty", "forty", "fifty",
    "sixty", "seventy", "eighty", "ninety" };
private static String[] TEENS_WORDS = {
    "ten", "eleven", "twelve", "thirteen", "fourteen",
    "fifteen", "sixteen", "seventeen", "eighteen", "nineteen" };

private static String getHundredWords(int num) {
    if (num > 999 || num < 0)
        throw new IllegalArgumentException(
            "Cannot get hundred word of a number not in the range 0-999");
    if (num == 0) return "zero";     
    String ret = "";
    if (num > 99) {
        ret += DIGIT_WORDS[num / 100] + " hundred ";
        num %= 100;
    }
    if (num < 20 && num > 9) {
        ret += TEENS_WORDS[num % 10];
    } else if (num < 10 && num > 0) {
        ret += DIGIT_WORDS[num];
    } else if (num != 0) {
        ret += TENS_WORDS[num / 10 - 1];
        if (num % 10 != 0) {
        ret += " " + DIGIT_WORDS[num % 10];
    }}

    return ret;
}