@1
MOV UP, DOWN

@4
L: MOV UP, ACC
JEZ Z
MOV ACC, DOWN
MOV UP, ACC
JEZ Z
MOV ACC, DOWN
JMP L
Z: MOV -999, DOWN

@8
L: ADD UP
JLZ E
MOV 1, RIGHT
ADD UP
JLZ E
MOV 1, RIGHT
JMP L
E: MOV -999, RIGHT
ADD 999
MOV ACC, DOWN
MOV 0, ACC

@9
L: ADD LEFT
JLZ E
JMP L
E: ADD 999
MOV ACC, DOWN
MOV 0, ACC
