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/* This is a prime-testing code. The page will only load on specific pages that
are meant to be shown. See Common.js for details. */
$('<div style="float: right; font-size:0.5em">Enter a number to test primality: <input type="text" id="myNumber" size="14" maxlength="15"><input type="button" value="Calculate" onclick="calculate(form)"><input type="text" id="myResult" name="result" size="55" value="" readonly placeholder="Enter a prime number here for testing!"></div>').appendTo('#PrimeTest_tag');
function calculate(form) {
var num = document.getElementById("myNumber").value;
num = num.replace(/\,/g,'');
num = parseInt(num,10);
var prime;
var x=Math.sqrt(num)+1;
var result;
if (isNaN(num) || num < 0) {
document.getElementById("myResult").value=(num + " is not a valid number! Try again!");
return;
}
//Switch block starts
switch (num) {
case 0:
result=("Uh......are you sure about number 0?");
break;
case 1:
result=("1 is not prime by definition. It has only 1 factor.");
break;
case 2:
result=("2 is a prime number! The only even one, sadly.");
break;
case 3:
var e = Math.floor((Math.random() * 10) + 1);
if (e == 8) {
result=("3 is a prime number! It's 3primetime3's favorite prime!");
} else {
result=("3 is prime!");
}
break;
case 37:
var e = Math.floor((Math.random() * 10) + 1);
if (e == 8) {
result=("You found an easter egg! It's Blueeighthnote's favorite prime!");
} else {
result=("37 is prime!");
}
break;
case 83:
var e = Math.floor((Math.random() * 10) + 1);
if (e == 8) {
result=("83 is a prime number! It's Minipop56's favorite prime!");
} else {
result=("83 is prime!");
}
break;
default:
for (var i=2;i<=x;i++) {
if (num % i === 0) {
prime="yes";
result=(num + " is not prime. It is divisible by " + i + ".");
break;
}
if (num % i !== 0) prime="no";
}
if (prime == "no") result=(num + " is prime!");
}
//End Switch block
document.getElementById("myResult").value = result;
}