@1
MOV UP, RIGHT

@2
MOV UP, ACC
JNZ NZ
MOV LEFT, ACC
ADD RIGHT
MOV ACC, DOWN
JMP END
NZ:
JGZ POS
MOV LEFT, DOWN
MOV RIGHT, NIL
JMP END
POS:
MOV LEFT, NIL
MOV RIGHT, DOWN
END:

@3
MOV UP, LEFT

@6
MOV UP, DOWN

@9
MOV UP, DOWN
