using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

public class Program

{

    public static void Main()

    {

        List<Dictionary<string, string>> dictionaries = new()

        {

            new Dictionary<string, string>

            {

                { "A", "a" },

                { "B", "b" }

            },

            new Dictionary<string, string>

            {

                { "C", "c" },

                { "D", "d" }

            },new Dictionary<string, string>

            {

                { "E", "e" },

                { "F", "f" }

            },

            new Dictionary<string, string>

            {

                { "A", "a" },

                { "B", "b" }

            },

            new Dictionary<string, string>

            {

                { "C", "c" },

                { "D", "d" }

            },new Dictionary<string, string>

            {

                { "E", "e" },

                { "F", "f" }

            }

        };

        Dictionary<string, string> result = new();

        foreach (Dictionary<string, string> dict in dictionaries)

        {

            foreach (KeyValuePair<string, string> pair in dict)

            {

                if (!result.ContainsKey(pair.Key))

                {

                    result.Add(pair.Key, pair.Value);

                }

                else

                {

                    result[pair.Key] += pair.Value;

                }

            }

        }

        foreach(KeyValuePair<string, string> pair in result)

        {

            Console.WriteLine($"{pair.Key}:{pair.Value}");

        }

    }

}