Description
This function will check any number to see if it is a prime number or not!
Parameters
num
Any number to be checked if it is prime or not
Function
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<?php
function is_prime($num){
for($i=$num;$i > 0;$i--){
$v = $num / $i;
if(!is_float($v)){
if($v != $num && $v != 1)
return FALSE;
}
}
return TRUE;
}
for($i = 1;$i<=100;$i++){
if(is_prime($i))
echo $i.' is prime<br>';
else
echo $i.' is not prime<br>';
}
?>Comments.
fabio July 2nd 2009
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Terrifying !!!!!!!!!!!!!!!!!!!Anonymous May 17th 2009
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That's horribly inefficient...