There are two versions of this program:
asciiadd.w: reads two characters, adds their ASCII values, and prints them out
add.w: like above, but treats 0 as origin, so 1+2 is 3 rather than c
Note that add.w uses the 0 in the top-left corner (which is operationally
equivalent to the star used elsewhere) for the origin. This character can be
changed to an arbitrary one, but 0 has been chosen because it gives the most
intuitive effect.
See cat.doc for general Wierd notes.