Resolving, reverse complement != complement according to the Bioinformatics website.

This kata only asks for complement DNA, no need to reverse it.

Because sentinal values are a bad idea for many reasons, though you probably already learned this in the 4 years since.

However I'm still bamboozeled as to why it returns Option<Vec<i32>> as opposed to Option<[i32; 3]>. This isn't an arbitrary list, it's exactly 3 elements. I might even expect Option<(i32, i32, i32).

OP solved it, closing

yes, I had to re-read the instructions 3x before I realized that it's not about "complemantary DNA" but about some arbitrary string manipulation ;)

Because the function does not always return a vector of integers.