aMinerTask

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

namespace aMinerTask
{
    class MainClass
    {
        public static void Main(string[] args)

        {
            var metals = new Dictionary<string, int>();

            while (true)
            {
                var input = Console.ReadLine();

                if (input.Equals("stop"))
                {
                    break;
                }

                var quantity = int.Parse(Console.ReadLine());


                if ( ! metals.ContainsKey(input) )
                {
                    metals[input] = 0;
                }
                metals[input] += quantity;

            }

            foreach (var pair in metals)
            {
                Console.WriteLine($"{pair.Key} -> {pair.Value}");
            }
        }
    }
}