Letters Combinations

using System;

namespace LettersCombination
{
    class Program
    {
        static void Main(string[] args)
        {
            char x = char.Parse(Console.ReadLine());
            char y = char.Parse(Console.ReadLine());
            char z = char.Parse(Console.ReadLine());

            int counter = 0;

            for (int i = x; i <= y; i++)
            {
                for (int k = x; k <= y; k++)
                {
                    for (int j = x; j <= y; j++)
                    {
                        if (i != z && k != z && j != z)
                        {
                            Console.Write($"{(char)i}{(char)k}{(char)j} ");
                            counter++;
                        }
                    }
                }
            }
            Console.WriteLine(counter);
        }
    }
}