Converting numbers to words in Java

Question

My program is to convert numbers between 0 and 100 to words. I'm not sure which strategy would be best to go about this but I would like to use math operators like modules, etc.This is what I've got so far.

package project.pkg1;

import java.util.Scanner;

public class Project1 {
public static final int MINUMUN_NUMBER = 0;
public static final int MAXIMUM_NUMBER = 100;
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
int num, x;
do{
    System.out.println("Enter a number between 0 and 100: ");
    num = keyboard.nextInt();

} while ((num < 0) || (num > 100));
if(num == 0)
        System.out.println("zero");
if(num == 100)
        System.out.println("one hundred");

I don't want to use the if(num == x) every time. My validation trap to make sure it is between 0 and 100 works fine. I'm just not sure how to approach the rest of it. This is what I can get to print:

run:
Enter a number between 0 and 100: 
-1
Enter a number between 0 and 100: 
101
Enter a number between 0 and 100: 
34
BUILD SUCCESSFUL (total time: 23 seconds)

I need that 34 to print "thirty four" Any feedback would be greatly appreciated!

This is a tedious task. I would recommend writing down numbers and their matching words to find similarities for cases. There will be many `if` statements involved. — But I'm Not A Wrapper Class, Feb 21 '14 at 20:44
not necessarily if statements, e.g. if the words are stored as array elements with the numbers as indices. — La-comadreja, Feb 21 '14 at 20:45
Have a Map for basic and irregular cases (1->one, 2->two, ...); try to use rules for combinations (e.g. 46 = (40) forty + (6) six). — qqilihq, Feb 21 '14 at 20:45
not a duplicate because 1-100 is a special case that is more manageable when things are done by hand. — La-comadreja, Feb 21 '14 at 20:47
I remember in university, someone wrote a 100 swich case block, that was so funny :-) — Leo, Feb 21 '14 at 20:48

score 1 · Answer 1 · answered Feb 21 '14 at 20:48

1

You should look at what the pattern is for numbers from 0 to 100. Here is what you would find:

single digit numbers: pull from String[] digit = {"zero", "one", two, ... , "ten" }
for teens pull from String[] teen = {"eleven", "twelve", ... ,"nineteen"}
for larger numbers divide by 10 and pull from {"twenty", "thirty", ... "ninety"}; then, if number has a remainder when divided by ten, add digit portion "-" + pull from digit above.

answered Feb 21 '14 at 20:48

ErstwhileIII

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How do I get it to divide by ten and then add the ones digit? – user3338808 Feb 21 '14 at 20:51

score 0 · Answer 2 · answered Feb 21 '14 at 20:44

0

You might as well create separate variables for the numbers from 1-19 and 100. As for 20-99, these have prefixes and suffixes that can be combined using string concatenation and can be identified through the first and last digits.

answered Feb 21 '14 at 20:44

La-comadreja

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Yeah I figured I would do the 1-19, 20-99, 100 variables, but I'm not sure how to set them and how to combine them. I'm sorry, I'm very new to coding. – user3338808 Feb 21 '14 at 20:48
try something and post another question with your work, if you'd like. – La-comadreja Feb 21 '14 at 20:49

score 0 · Answer 3 · answered Feb 21 '14 at 20:59

public class NumbersToWords {

    private static final String[] NUMBERS = {
        "zero",
        "one",
        "two",
        "three",
        "four",
        "five",
        "six",
        "seven",
        "eight",
        "nine",
        "ten",
        "eleven",
        "twelve",
        "thirteen",
        "fourteen",
        "fifteen",
        "sixteen",
        "seventeen",
        "eighteen",
        "nineteen",
        "one hundred"
    };

    private static final String[] TENS = {
        "twenty",
        "thirty",
        "fourty",
        "fifty",
        "sixty",
        "seventy",
        "eighty",
        "ninty"
    };

    public static String numberToWord( final int number ){
        if ( number < 0 )
            throw new IllegalArgumentException( "Number too low" );
        if ( number > 100 )
            throw new IllegalArgumentException( "Number too high" );
        if ( number < 20 )
            return NUMBERS[number];
        if ( number == 100 )
            return NUMBERS[20];
        return TENS[number/10-2] + ((number%10>0)?(" "+NUMBERS[number%10]):"");
    }

    public static void main(String[] args) {
        for ( int i = 0; i <= 100; ++i )
            System.out.println( numberToWord( i ) );
    }
}

I really appreciate the code! But, I'm trying to get what your code just output to be my answer. I need it to output Enter a number between 0 and 100: 34 Thirty Four — user3338808, Feb 21 '14 at 21:10

Converting numbers to words in Java

3 Answers3