- Find program that turns any block configuration into a single stack that spells “UNIVERSAL.”
- CS = name of top block on stack, or F.
- TB = name of topmost correct block on stack.
- NN = name of next block that needs to be on stack.
- MS x = if x is on table then move to stack, else return F.
- MT x = if x is on stack then move the block on top of tack to table.
- EQ x y, NOT x
- DU x y = do x until y returns true.
- What happened? After 10 generations, with 166 test problems, the program found
(EQ (DU (MT CS)(NOT CS)) (DU (MS NN) (NOT NN)))
which solved all 166 problems.