@0
I: MOV UP, ACC
T: SAV
SUB RIGHT
JGZ P
MOV RIGHT, ACC
O: MOV ACC, RIGHT
JEZ I
SWP
JMP T
P: ADD RIGHT
JMP O

@1
S: MOV RIGHT, DOWN
L: MOV UP, ACC
JEZ Z
MOV ACC, LEFT
MOV ACC, LEFT
MOV LEFT, ACC
MOV ACC, DOWN
MOV ACC, DOWN
JMP L
Z: MOV 999, LEFT
MOV NIL, LEFT
MOV LEFT, ACC
MOV ACC, DOWN
MOV ACC, DOWN

@2
MOV UP, LEFT

@4
I: MOV UP, ACC
T: SAV
SUB UP
JLZ P
MOV UP, ACC
O: MOV ACC, DOWN
JEZ I
SWP
JMP T
P: ADD UP
JMP O

@8
MOV UP, DOWN
