The last two digits are sorted alphabetically by name. For example, Cao Cao's pinyin prefix is cc and Zhen Chen's pinyin prefix is cz, so the student numbers of these two people can be sequentially numbered as11... 011... 02.
The five digits in the middle refer to the specialty number, such as 200 1 1, which refers to a specialty and corresponds to a professional name.
Let's look at an example: Cao Cao's student number is 1 11,and the first two digits are "11",which means that Cao Cao is in grade 201.