@1
O: MOV ACC, RIGHT
   MOV UP, ACC
   JNZ O
   MOV ACC, DOWN
E: MOV UP, ACC
   MOV ACC, DOWN
   JNZ E
   MOV DOWN, ACC

@4
   MOV UP, RIGHT
I: MOV ACC, DOWN
   MOV UP, ACC
   JNZ I
   MOV RIGHT, UP
O: MOV DOWN, ACC
   MOV ACC, RIGHT
   JNZ O

@5
   MOV LEFT, NIL
O: MOV UP, ACC
   MOV ACC, DOWN
   JNZ O
   MOV ACC, LEFT
E: MOV LEFT, ACC
   MOV ACC, DOWN
   JNZ E

@7
MOV UP, DOWN
