From the keyboard input of a class () out of a class of not more than 30 students of a certain subject, when the input result is negative, the input end, respectively, to implement the following function
(1) statistics fail number and print the students failed to pass the list
(2) the statistical results in the number of students in the class average and above, and print the list of the students
(3) statistics the number of students in each band, and percentage