The two sets of papers are exactly the same. There are two sets of exams in the whole city.
However, if you are in No.1 Middle School, the formal exam (that is, the exam for practicing grading) is from the middle school attached to Harbin Normal University (that is, the exam for joint examination).
The second set only takes the test paper of Harbin No.3 Middle School. There is no need to practice grading, and it is not as formal as the first set of exams. So this is just an exercise.