Answer 1

As much as i am getting u....solution is like
<?
$pin=$_POST ['PIN'];

//other code
// suppose array available[ ]

for ($i=0; $i <=available.length; $i++)
{

if (available [i]==$pin)
{
$flag=1; break;
}

}

if (flag)
echo " available ";

else
echo " not available ";

//other code

?>