This time we’re digging one or more ponds deeper. It took a long time for me to think of this solution.

In part 1 it’s 1 layer deeper, in part 2 2 layers, and in part 3 as many layers as there’s room for.

Part 3 might get a little crazy…

I’m using a mechanism, where I can look at 3 characters and write in a 4th position. In part 3 I have a 5th head, keeping track of whether I need to dig deeper. I also write extra characters, to make sure I stop at the end of each line.

All my code .