classes:  lecturer. Because of the peculiarities of the subject, when the code should be returned to the screen for students to review, long code time, moreover, even if the student understands the code, it is difficult to visualize the characters correctly.  curriculum. Because of the peculiarities of the subject, when the code should be returned to the screen for students to review, long code time, moreover, even if the student understands the code, it is difficult to visualize the characters correctly.  facility. Because of the peculiarities of the subject, when the code should be returned to the screen for students to review, long code time, moreover, even if the student understands the code, it is difficult to visualize the characters correctly.  general. Because of the peculiarities of the subject, when the code should be returned to the screen for students to review, long code time, moreover, even if the student understands the code, it is difficult to visualize the characters correctly.