student_academy

students = {}

n = int(input())

for _ in range(n):
    name = input()
    grade = float(input())

    if name not in students:
        students[name] = []
    students[name].append(grade)

students = {k: sum(v)/len(v) for k, v in students.items() if sum(v)/len(v) >= 4.5}
sorted_students = sorted(students.items(), key=lambda kvp: -kvp[1])
for k, v in sorted_students:
    print(f"{k} -> {v:.2f}")