<!DOCTYPE html>
<html lang="en">
<head>
<title>Prime factors calculator</title>
</head>
<body>
<h1>Prime factors calculator</h1>
<table>
<tbody>
<tr>
<th><label for="inputField">Please enter a number:</label></th>
<td><input id="inputField"> <input type="button" value="Calc" onclick="CalcPrimeFactors()"
id="Button1" name="Button1"></td>
</tr>
<tr>
<th><label for="outputField">The factors are:</label></th>
<td><input id="outputField" size="60" disabled="disabled"></td>
</tr>
</tbody>
</table>
<h3>Hint:</h3>
<p>try 12313123123123 or 12313123123123123123 for long running calculations ! </p>
<script type="text/javascript">
// calc prime factors
function CalcPrimeFactors() {
var inputText, outputText;
var prime; // try this factor (only primes will match!)
var number; // product of the remaining factors
document.getElementById("outputField").value = "wait...";
outputText = "";
inputText = document.getElementById("inputField").value;
if ((inputText == null) || (inputText.length == 0) || (inputText == "0"))
return;
prime = 2; // start with 2
number = parseInt(inputText);
while ((number > 1) && (prime * prime <= number)) {
if (number % prime != 0) {
// try the next factor (slowly)
prime += 1;
} else {
// found a factor !
outputText = outputText + " " + prime;
number = number / prime;
} // if
} // while
if (number > 1) {
// the last factor (a prime) is here.
outputText = outputText + " " + number;
}
document.getElementById("outputField").value = outputText;
} // CalcPrimeFactors
</script>
<hr />
<p>This sample uses HTML and Javascript synchronously.</p>
<p>This page is part of the <a href="http://ajaxaspects.blogspot.com/">http://ajaxaspects.blogspot.com/</a>
project.</p>
<hr />
</body>
</html>
This page is part of the http://www.mathertel.de/ web site.
For updates and discussions see http://ajaxaspects.blogspot.com/.