title: Calculating factorials in C#
body: <p>I am trying to write a program that will take the users input value and asks whether they want to calculate the value of the numbers 1 to n or the factorial of n!
  This is what I have so far</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  
  namespace Project_2_Part_B
  {
      class Program
      {
          static void Main(string[] args)
          {
              var Fkeylow = "f";
              var FkeyCap = "F";
              var Skeylow="s";
              var SkeyCap="S";
              int n = 0;
              long factorial = n;
  
              Console.WriteLine("Input a value n");
              n = Convert.ToInt32(Console.ReadLine());
  
              Console.WriteLine("Do you want to calculate factorial or sum");
              Console.WriteLine("Enter F or S");
  
              var A = Console.ReadLine();
  
              if (A == Fkeylow)
                  Console.WriteLine();
  
              if (A == FkeyCap)
                  Console.WriteLine();
  
              var B=Console.ReadLine();
  
              if (B == Skeylow)
                  Console.WriteLine();
  
              if (B == SkeyCap)
                  Console.WriteLine();
  
              Console.WriteLine("Press any key to close...");
              Console.ReadLine();
          }
      }
  }
  </code></pre>
  
  <p>My issue is with the syntax of the calculation to make the code execute the n*(n-1) while n>1.</p>