Сума от две числа

using System;

namespace dwdwdwdwDD
{
    class Program
    {
        static void Main(string[] args)
        {
            var startNum = int.Parse(Console.ReadLine());
            var endNum = int.Parse(Console.ReadLine());
            var magicNum = int.Parse(Console.ReadLine());

            var count = 0;
            var c = 0;

            for (int a = startNum; a <= endNum; a++)
            {
                for (int b = startNum; b <= endNum; b++)
                {
                    c = a + b;
                    count++;
                    if (c == magicNum)
                    {
                        Console.Write($"Combination N:{count} ({a} + {b} = {c})");
                        Environment.Exit(0);
                    }

                }

            }
            Console.WriteLine($"{count} combinations - neither equals {magicNum}");

        }
    }
}