说明：  费诺编码的步骤: A 将概率按从大到小的顺序排列 B 按编码进制数将概率分组，使每组概率和尽可能接近或相等。 C 给每组分配一位码元 D 将每一分组再按同样原则划分，重复b和c，直到概率不再可分为止
(Fenno coding steps: A will be by the smallest probability of the order B-band number will be coded according to the probability of packet, so that each probability and as close as possible or equivalent. C allocation to each element D 1 yards of each packet and then the same principle of division, repeat b and c, until the probability is no longer so far can be divided into)