@1
A: MOV ACC, RIGHT
MOV UP, ACC
JNZ A
MOV ACC, DOWN
B: MOV UP, ACC
MOV ACC, DOWN
JNZ B
MOV DOWN, NIL

@4
MOV RIGHT, NIL
MOV UP, RIGHT
B: MOV ACC, DOWN
MOV UP, ACC
JNZ B
MOV RIGHT, UP
MOV ACC, RIGHT

@5
MOV DOWN, LEFT
MOV LEFT, NIL
P: MOV UP, ACC
MOV ACC, DOWN
JNZ P
MOV ACC, LEFT
MOV LEFT, DOWN

@7
MOV ACC, UP
P: MOV UP, ACC
MOV ACC, DOWN
JNZ P
MOV UP, NIL
Q: MOV LEFT, ACC
MOV ACC, DOWN
JNZ Q
