Christmas Challenge 2021
This is a bit tricky, as Michael Banks said to Mary Poppins. To save two more bytes, I have taken out the string manipulation part of the loop and instead used indirection operations to do a memory peek where the tree string is stored. This meant that I needed to have the tree string stored somewhere in memory. In order to prevent bytes being used in DIMming a memory block, I used the only variable in BBC BASIC already pointing to a location in memory which would be useable - @%, which is normally the formatting variable for PRINT, but defaults to &90A, or 2314, a nice place to store 14 bytes of tree!