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

namespace ClubParty
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());

            var hall = new Dictionary<string, List<int>>();

            var line = Console.ReadLine().Split(' ' , StringSplitOptions.RemoveEmptyEntries).Reverse().ToList();

            int capacity = 0;

            for (int i = 0; i < line.Count; i++)
            {

                if (int.TryParse(line[i] , out  int number) && hall.Count > 0)
                {
                    capacity += number;
                    if(capacity <= n)
                    {
                            var hallNumber = hall.Keys.First();
                            hall[hallNumber].Add(int.Parse(line[i]));
                    }
                    else if (hall.Count > 0)
                    {
                        foreach (var (key, value) in hall)
                        {
                            if (value.Count > 0)
                            {
                                Console.Write($"{key} -> ");
                                Console.Write(string.Join(", ", value));
                                Console.WriteLine();
                                hall.Remove(key);
                                capacity = 0;
                                break;
                            }
                            else
                            {
                                capacity -= number;
                            }

                        }
                        if (hall.Count > 0 && number <= n)
                        {
                            var hallNumber = hall.Keys.First();
                            hall[hallNumber].Add(int.Parse(line[i]));
                            capacity += number;
                        }
                    }
                }

                else
                {
                    if (!hall.ContainsKey(line[i]) && char.TryParse(line[i] , out char result))
                    {
                        if (char.IsLetter(result))
                        {
                            hall[line[i]] = new List<int>();
                        }
                    }
                }
            }
        }
    }
}