Convert number to words java

Write a code to Convert number to words . example  ip 15  op : fifteen

ip : 1234  op : one thousand and thirty four

Algorithm : When we detect a number at any place how to convert to a word. Obviously we need to store it.
See usage of Data Structure in java and Data Structure in c++ .
See usage of static string in java.

Step 1 ) Create array of ones[20] = {“zero”, “one”, “two”, …, “nineteen”};
Step 2) Create array of tens[10] = {“”, “ten”, “twenty”, …, “ninety”};
Step 3) Divide number by 1000, 100, 20 and convert it.
Step 4) Print it.

Convert number to words C++ solution

#include<iostream>
#include<string>
using namespace std;

string units [20] = {"","One ","Two ","Three ","Four ", "Five ","Six ","SEven ","Eight ","Nine ","Ten ","Eleven ", "Twelve ","Thirteen ","Fourteen ","Fifteen ","Sixteen ","Seventeen ","Eighteen ","Nineteen "};
string tens[] = {"","","Twenty ","Thirty ","Fourty ","Fifty ","Sixty ","Seventy ","Eighty ","Ninty "};
string digits[] = {"","","","Hundred ","Thousand ","Thousand ","Lakh ","Lakh ","Crore "};

string getOneDigit(int val, int index) { 
 if(val < 10) {
  string res = units[val];
  if(val != 0) {
    res = res + digits[index];
  }
  return res;
  }
  return "";
}

string getTensDigit(int val, int index) {
 if(val < 10) {
 string res = tens[val] + digits[index];
 return res;
 } 
 return "";
}

string getTwoDigit(int val, int index) {
 string res = ""; int temp = val;
 if(val < 20) {
  res = units[val] + res;
 }
 else {
  res = getOneDigit(val%10,0) + res;
  val = val /10;
  res = getTensDigit(val %10, 1) + res;
 }
 if(temp != 0) 
  res = res + digits[index];
  return res;
}

string convertToString(int n) {
 string result = "";
 int i = 1, r;
 while(n) {
 if(i != 3) {
   r = n %100;
   result = getTwoDigit(r,i) + result;
   n = n / 100;
   i = i+2;
 }
 else if(i == 3) {
   r = n %10;
   result = getOneDigit(r, i) + result;
   n = n / 10;
   i++;
 }
 }

 return result;
}
int main() {
 int n, t;
 cin>>t;
 while(t--) {
 cout<<"Entet the number to be converted: ";
 cin>>n;
 cout<<"Result : "<<convertToString(n)<<endl;
 }
 return 0;
}

Optimised Solution by : Rahul Goyal (B.Tech in CSE, Amrita School of Engineering)
See OP : https://ideone.com/FT5Rxv

Convert number to words java solution

Java solution with Scanner to word utility ,  which helps user  to input number  in this program.
See why we have used static string to initialize specialNames, tenseNames.

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import java.util.Scanner;
class TestClass {
 private static final String[] specialNames = {
 ""," thousand"," million"," billion"," trillion"," quadrillion",
" quintillion"
 };
 
 private static final String[] tensNames = {
 ""," ten"," twenty"," thirty"," forty"," fifty"," sixty"," seventy",
" eighty"," ninety"
 };
 
 private static final String[] numNames = {
 ""," one"," two"," three"," four"," five"," six"," seven"," eight",
 " nine"," ten"," eleven"," twelve"," thirteen"," fourteen"," fifteen",
 " sixteen"," seventeen"," eighteen"," nineteen"
 };
 
 private String convertLessThanOneThousand(int number) {
 String current;
 if (number % 100 < 20){
 current = numNames[number % 100];
 number /= 100;
 }
 else {
  current = numNames[number % 10];
  number /= 10;
  current = tensNames[number % 10] + current;
  number /= 10;
 }
  if (number == 0) return current;
  return numNames[number] + " hundred and" + current;
 }
 
public String convert(int number) {
if (number == 0) { return "zero"; }
  String prefix = ""; 
  if (number < 0) {
  number = -number;
  prefix = "negative";
 }

 String current = "";
 int place = 0;
 
  do {
  int n = number % 1000;
  if (n != 0){
  String s = convertLessThanOneThousand(n);
  current = s + specialNames[place] + current;
  }
  place++;
  number /= 1000;
 }   while (number > 0);
 
 return (prefix + current).trim();
 }
 
public static void main(String[] args) throws Exception {
  TestClass obj = new TestClass();
  Scanner sc = new Scanner(System.in);
  int n = sc.nextInt();
  System.out.println(obj.convert(n));
 }
}