using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;

namespace DICT_LMBD_And_LINQ
{
    class Program
    {
        public static void Main()
        {
            var gradesBy = new Dictionary<string, List<double>>();

            int n = int.Parse(Console.ReadLine());
            for (int i = 0; i < n; i++)
            {
                string name = Console.ReadLine();
                double grade = double.Parse(Console.ReadLine());

                if (gradesBy.ContainsKey(name) == false)
                {
                    gradesBy.Add(name, new List<double>());
                }

                gradesBy[name].Add(grade);
            }

            var sorted = gradesBy.Where(g => g.Value.Average() >= 4.50).OrderByDescending(g => g.Value.Average()).ToDictionary(x => x.Key, x => x.Value);

            foreach (var person in sorted)
            {
                Console.WriteLine("{0} -> {1:f2}", person.Key, person.Value.Average());
            }
        }
    }
} // .