def task_8_18():
i = 0
while wall_is_beneath():
if not wall_is_above():
move_up()
while True:
if not cell_is_filled():
fill_cell()
else:
i += 1
if wall_is_above():
break
move_up()
while not wall_is_beneath():
move_down()
else:
fill_cell()
move_right()
mov('ax', i)
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