Написание цифр прописью, на английском языке

<SCRIPT LANGUAGE="JavaScript">
<!-- Original: jc491403@altavista.com -->
<!-- Begin
var n = "";
function validate(input) {
if (input.length == 0) {
alert ('Please Enter A Number.');
document.myform.textver.value = "";
return true;
}
else convert(input);
}
function d1(x) { // single digit terms
switch(x) {
case '0': n= ""; break;
case '1': n= " One "; break;
case '2': n= " Two "; break;
case '3': n= " Three "; break;
case '4': n= " Four "; break;
case '5': n= " Five "; break;
case '6': n= " Six "; break;
case '7': n= " Seven "; break;
case '8': n= " Eight "; break;
case '9': n= " Nine "; break;
default: n = "Not a Number";
}
return n;
}
function d2(x) { // 10x digit terms
switch(x) {
case '0': n= ""; break;
case '1': n= ""; break;
case '2': n= " Twenty "; break;
case '3': n= " Thirty "; break;
case '4': n= " Forty "; break;
case '5': n= " Fifty "; break;
case '6': n= " Sixty "; break;
case '7': n= " Seventy "; break;
case '8': n= " Eighty "; break;
case '9': n= " Ninety "; break;
default: n = "Not a Number";
}
return n;
}
function d3(x) { // teen digit terms
switch(x) {
case '0': n= " Ten "; break;
case '1': n= " Eleven "; break;
case '2': n= " Twelve "; break;
case '3': n= " Thirteen "; break;
case '4': n= " Fourteen "; break;
case '5': n= " Fifteen "; break;
case '6': n= " Sixteen "; break;
case '7': n= " Seventeen "; break;
case '8': n= " Eighteen "; break;
case '9': n= " Nineteen "; break;
default: n= "Not a Number";
}
return n;
}
function convert(input) {
var inputlength = input.length;
var x = 0;
var teen1 = "";
var teen2 = "";
var teen3 = "";
var numName = "";
var invalidNum = "";
var a1 = ""; // for insertion of million, thousand, hundred  
var a2 = "";
var a3 = "";
var a4 = "";
var a5 = "";
digit = new Array(inputlength); // stores output
for (i = 0; i < inputlength; i++) {
// puts digits into array
digit[inputlength - i] = input.charAt(i)};
store = new Array(9); // store output
for (i = 0; i < inputlength; i++) {
x= inputlength - i;
switch (x) { // assign text to each digit
case x=9: d1(digit[x]); store[x] = n; break;
case x=8: if (digit[x] == "1") {teen3 = "yes"}
  else {teen3 = ""}; d2(digit[x]); store[x] = n; break;
case x=7: if (teen3 == "yes") {teen3 = ""; d3(digit[x])}
  else {d1(digit[x])}; store[x] = n; break;
case x=6: d1(digit[x]); store[x] = n; break;
case x=5: if (digit[x] == "1") {teen2 = "yes"}
  else {teen2 = ""}; d2(digit[x]); store[x] = n; break;
case x=4: if (teen2 == "yes") {teen2 = ""; d3(digit[x])}  
  else {d1(digit[x])}; store[x] = n; break;
case x=3: d1(digit[x]); store[x] = n; break;
case x=2: if (digit[x] == "1") {teen1 = "yes"}
  else {teen1 = ""}; d2(digit[x]); store[x] = n; break;
case x=1: if (teen1 == "yes") {teen1 = "";d3(digit[x])}  
  else {d1(digit[x])}; store[x] = n; break;
}
if (store[x] == "Not a Number"){invalidNum = "yes"};
switch (inputlength){
case 1: store[2] = "";  
case 2: store[3] = "";  
case 3: store[4] = "";  
case 4: store[5] = "";
case 5: store[6] = "";
case 6: store[7] = "";
case 7: store[8] = "";
case 8: store[9] = "";
}
if (store[9] != "") { a1 =" Hundred, "} else {a1 = ""};
if ((store[9] != "")||(store[8] != "")||(store[7] != ""))
{ a2 =" Million, "} else {a2 = ""};
if (store[6] != "") { a3 =" Hundred "} else {a3 = ""};
if ((store[6] != "")||(store[5] != "")||(store[4] != ""))
{ a4 =" Thousand, "} else {a4 = ""};
if (store[3] != "") { a5 =" Hundred "} else {a5 = ""};
}
// add up text, cancel if invalid input found
if (invalidNum == "yes"){numName = "Invalid Input"}
else {
numName = store[9] + a1 + store[8] + store[7]  
+ a2 + store[6] + a3 + store[5] + store[4]  
+ a4 + store[3] + a5 + store[2] + store[1];
}
store[1] = ""; store[2] = ""; store[3] = "";  
store[4] = ""; store[5] = ""; store[6] = "";
store[7] = ""; store[8] = ""; store[9] = "";
if (numName == ""){numName = "Zero"};
document.myform.textver.value = numName;
return true;
}
// End -->
</script>

<center>
Введите число от 0 до 999,999,999

<form name="myform">
<table border=0>
<tr>
<td>Число:</td>
<td><input name="numver" size=9 maxlength=9> <input onclick="return validate(document.myform.numver.value)" type="button" value="Написать число"></td>
</tr>
<tr>
<td>Число прописью:</td>
<td><input name="textver" size=50 maxlength=50></td>
</tr>
<tr>
<td align=middle colspan=2></td>
</tr>
</table>
</form>
</center>