There are two letters before and after the old EMS single number, and the continuity is generally the same. The middle 9 digits, the first 8 digits are continuous. The last encrypted number is calculated according to the first eight numbers.

The calculation rules are as follows:

1, X= first *8+ second *6+ third *4+ fourth *2+ fifth *3+ sixth *5+ seventh *9+ eighth *7.

2. The remainder obtained by calculating x/11= y.

3. calculate z =11-y.

When Z= 10, the last digit is 0.

When Z= 1 1, the last digit is 5.

When z

For example, your first single number ek702111856cs.

x = 7 * 8+0 * 6+2 * 4+ 1 * 2+ 1 * 3+ 1 * 5+8 * 9+5 * 7 = 18 1

The remainder y of X/ 1 1 is 5.

Z= 1 1-5=6

Z< 10, and the last digit is 6.

In the new EMS, the two letters before and after the single number are replaced by numbers, but the continuity is basically the same. The algorithm before and after removal is the same.