courses = {}
while True:
    command = input().split(" : ")
    course_name = command[0]
    if course_name == 'end':
        break
    student_name = command[1]
    if course_name not in courses.keys():
        courses[course_name] = [student_name]
    else:
        courses[course_name] += [student_name]
for course_name, registered_students in courses.items():
    print(f"{course_name}: {len(registered_students)}")
    print(f'-- {" ".join(courses[course_name])}')