Questions for students (2nd weeks)

August 31

Write method, parse the result based on the user-defined string. It is known that the string given by the user only contains numbers, addition, subtraction, multiplication, division symbols, and is a legal mathematical expression. For example:

35 + 3

2*3 + 3-4*6

-7 + 10*3/4 + 6*2-7/2

 

September 1

Think of a good example to explain the concept of polymorphism.

 

September 2

Write a student category, which includes the student ID, name, and class attributes, and write a simulated method to add, delete, modify, and query students.

 

September 3

WriteCodeRealize the use of polymorphism and polymorphism.

 

September 4

Add a method to the student class to simulate obtaining information about all students, requiring students to be represented by student objects and all students to be represented by arraylist objects. Under normal circumstances, student information is obtained from the database and must be dynamically generated in the method. Then write a test method to obtain the student information and output it to the console.