ThatsNinja

Have you considered the implementation of a grid of textboxes? Something like: https://github.com/denisraslov/react-spreadsheet-grid

Just off the top of my head it doesn't sound super difficult to start with a 1*1 and expand it as a user enters codes out to the maximum row...

I have a branch ready to PR for this change. It's based off of the branch in PR #6 though, so I'd like to settle that PR before opening this...

(See PR #9)

I'm still puzzling over this one a bit, working through the code to see how everything hangs together. I have some tests written around this, but I'm not certain yet...