Problem 4
A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 
99.
Find the largest palindrome made from the product of two 3-digit numbers.
Solution
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Project Euler 004</title>
</head>
<body >
<script type="text/javascript">
function IsPalindrome(number)
{
numberStr = number.toString();
// simple palindrome test
// we only have to go through the first
// half of the letters
for (c = 0; c < numberStr.length-c; c++)
{
if (numberStr[c] !=
numberStr[numberStr.length-c-1]) {
return false;
}
}
return true;
}
answer = 0
//here’s a familiar loop
for(i = 100; i < 1000; i++)
{
for(j = i; j < 1000; j++)
{
product = i*j;
if ((product > answer)
&& IsPalindrome(product))
{ answer = product; }
}
}
document.write("<b>" + answer + "</b>");
</script>
</body>
</html>
Discussion
Nothing too special here, but this is the one solution that didn’t use some sort of built in “reverse” function. Still works. 
If you have questions, leave a comment or please find me on Twitter (@azzlsoft) or email (rich@azzlsoft.com).
azzlsoft.com 
for (c = 0; c < numberStr.length – c; c++)
is not valid.. error
Talbot, thanks for finding that. Try retyping the line in question. It appears as though the “-” (hyphen/minus) has been turned into a “–” (en dash) by Windows Live Writer. It’s a very subtle difference.