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

namespace _06Courses
{
    class Program
    {
        static void Main(string[] args)
        {
            var cousesCount = new Dictionary<string, int>();
            var students = new Dictionary<string, List<string>>();

            string command = string.Empty;

            while ((command = Console.ReadLine()) != "end")
            {
                var input = command.Split(" : ").ToArray();
                string courseName = input[0];
                string studentName = input[1];

                if (!students.ContainsKey(courseName))
                {
                    students[courseName] = new List<string>();
                    students[courseName].Add(studentName);
                    cousesCount[courseName] = 1;
                }
                else if(!students[courseName].Contains(studentName))
                {
                    students[courseName].Add(studentName);
                    cousesCount[courseName] += 1;
                }
            }

            foreach (var kvp in cousesCount)
            {
                Console.WriteLine($"{kvp.Key}: {kvp.Value}");

                foreach (var student in students)
                {
                    Console.WriteLine($"-- {student.Value}");
                }
            }

        }
    }
}