Maximum Year in Expiry Date of Credit Card

Question

Various online services have different values for maximum year of expiry, when it comes to Credit Cards.

For instance:

• Basecamp: +15 years (2025)

Answer 1

While the second example runs twice as quickly as the first you are still getting the date and extracting the year from it 20 times rather than 40 times. A better unrolling of the loop is:

$StartDate=date('Y');
$EndDate=$StartDate+21;
for($i=$StartDate;$i<$EndDate;$i++){
    echo "".substr($i,2)."\n";

That will be about 20 times faster than the twice as fast example and also addresses a minor bug in the original code in that the year could change from one fetching of the date to the next leading to unexpected, though in this case harmless, results.