I have a couple of questions regarding what you are doing. On the following line:

next if ( $last_digit == 5 or $last_digit = 0 );

did you mean:

next if ( $last_digit == 5 or $last_digit == 0 );

also to make it run even faster you might want to look to have it only check from $input to sqrt($input). If it does not fail up to the
sqrt($input) it will not fail past that point.

-Enlil

In reply to Re: YAPNC: Yet another prime number checker? by Enlil
in thread YAPNC: Yet another prime number checker? by snafu

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