02. Letters Change Numbers

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace judge
{
    class judge
    {
        static void Main(string[] args)
        {
            string pattern = @"\s+";
            List<string> numsList = Regex.Split(Console.ReadLine(), pattern).Where(s => !string.IsNullOrWhiteSpace(s)).ToList();
            double result = 0;
            for (int i = 0; i < numsList.Count; i++)
            {
                double num = double.Parse(numsList[i].Substring(1, numsList[i].Length - 2));
                int firstLetter = char.ToUpper(numsList[i][0]) - 64;
                int lastLetter = char.ToUpper(numsList[i][numsList[i].Length - 1]) - 64;
                if (char.IsUpper(numsList[i][0]))
                {
                    //Console.WriteLine("{0}/{1}={2}", num, firstLetter, num/ firstLetter);
                    num /= firstLetter;
                }
                else
                {
                    //Console.WriteLine("{0}*{1}={2}", num, firstLetter, num * firstLetter);
                    num *= firstLetter;
                }
                if (char.IsUpper(numsList[i][numsList[i].Length - 1]))
                {
                    //Console.WriteLine("{0}-{1}={2}", result, lastLetter, result - lastLetter);
                    num -= lastLetter;
                }
                else
                {
                    //Console.WriteLine("{0}+{1}={2}", result, lastLetter, result + lastLetter);
                    num += lastLetter;
                }
                result += num;
            }
            Console.WriteLine("{0:F2}", result);
        }
    }
}