Metric-Converter-Switch-Variant

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

namespace Metric_Converter
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = double.Parse(Console.ReadLine());
            var input = Console.ReadLine();
            var output = Console.ReadLine();

            switch(input)
            {
                case "mm":
                    n /= 1000;
                    break;
                case "cm":
                    n /= 100;
                    break;
                case "mi":
                    n /= 0.000621371192;
                    break;
                case "in":
                    n /= 39.3700787;
                    break;
                case "km":
                    n /= 0.001;
                    break;
                case "ft":
                    n /= 3.2808399;
                    break;
                case "yd":
                    n /= 1.0936133;
                    break;
            }


            switch (output)
            {
                case "mm":
                    n *= 1000;
                    break;
                case "cm":
                    n *= 100;
                    break;
                case "mi":
                    n *= 0.000621371192;
                    break;
                case "in":
                    n *= 39.3700787;
                    break;
                case "km":
                    n *= 0.001;
                    break;
                case "ft":
                    n *= 3.2808399;
                    break;
                case "yd":
                    n *= 1.0936133;
                    break;
            }
            Console.WriteLine($"{n:F8}");

        }
    }
}