Re: Trying to use substring to find a reverse complement in DNA,

[RichardK]

The condition on your for loop is the wrong way round, you need to use less than not greater than, here:-

$i>$length-1;

If you want to know how to fix these things for yourself try the basic debugging checklist

[AnomalousMonk]

... you need to use less than not greater than ...

I would say tryingnottofailmytes needs to use less-than-or-equal
    $i <= $length-1
as the for-loop condition in the OPed code.

[tryingnottofailmytes]

THANK YOU SO MUCH!!!! This is my problem, I get really close in my code (at least I think I do) and I can't find the problems and I freak out and get a terrible score...