Pseudocode with explanation

Trainers at Toms Athletic Club are encouraged to enroll new members. Write an application that allows Tom to enter the names of each of his 25 trainers and the number of new members each trainer has enrolled this year. Output is the number of trainers who have enrolled 0 to 5 members, 6 to 12 members, 13 to 20 members, and more than 20 members.