@1
A: MOV UP, DOWN
MOV RIGHT, ACC
SAV
L: SWP
MOV ACC, DOWN
SWP
MOV DOWN, ACC
JRO ACC

@2
MOV UP, LEFT

@4
MOV UP, ACC
L: SUB UP
MOV -4, UP
JLZ F
MOV 1, DOWN
JMP L
F: MOV -999, DOWN
ADD UP
MOV -8, UP
MOV ACC, DOWN

@7
MOV 0, ACC
L: ADD UP
JGZ L
ADD 999
MOV ACC, DOWN
MOV UP, RIGHT

@8
MOV LEFT, DOWN
