I think this solution is better then others :)

Wouldn't this return a DivideByZero exception during a vertical line?

Hi! It's about dynamic programming, the "top down" approach.

Hi! This is very clever. But I fail to imagine my self ever thinking of this. Can you please tell me how this style/techniqeu is called so I could learn it and practice it more?

I like how you incremented 'rot' when iterating the rotors instead of additionally iterating the remaining characters for every rotor like I did.

Only thing I don't like about it is that you concatenate the result strings in every rotor iteration. Would have been more performant to allocate char arrays and replace the elements then create a string from it when it's finished.