How to check whether a number is Prime or not?

1.	How to check whether a number is Prime or not?
Answer» Example FUNCTION IsPrime($n) { for($X=2; $x&LT;$n; $x++) { if($n %$x ==0) { return 0; } } return 1; } $a = IsPrime(3); if ($a==0) echo 'Its not PRIME Number.....'."\n"; else echo 'It is Prime Number..'."\n";

Answer»

Example

FUNCTION IsPrime($n) {

for($X=2; $x&LT;$n; $x++)

{

if($n %$x ==0) {

return 0;

}

return 1;

}

$a = IsPrime(3);

if ($a==0)

echo 'Its not PRIME Number.....'."\n";

else

echo 'It is Prime Number..'."\n";

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