Example  for getting largest number in an array:

$array = array(20,18,95,45,48);
 
$max1 = 0;
$max2 = 0;
 
for($i=0; $i<count($array); $i++)
{
    if($array[$i] > $max1)
    {
      $max2 = $max1;
      $max1 = $array[$i];
    }
    else if($array[$i] > $max2)
    {
      $max2 = $array[$i];
    }
}

echo "Largest  value = ".$max1;
echo "<br />"; 
echo "Second Largest Value = ".$max2;

Output:

Maximum value = 95
Second maximum Value = 48