title: C# . Cannot implicitly convert int to ulong
body: <p>I worte the following code in c# and it says cannot implicitly convert type ulong into int what can i do to correct and why did this happen</p>
  
  <pre><code> Random rnd = new Random();
  
          ulong a;
          ulong input;
          int c1 = 0;
          int c2;  
  
          a = (ulong)rnd.Next(1, 101);
  
          Console.WriteLine("Welcome to the random number checker.\n" 
              +"You can guess the number. Try and find in how many tries you can get it right. "
              +"\n\t\t\t\tGame Start");
  
          do
          {
              Console.WriteLine("Enter your guess");
              input = Console.ReadLine();
              c1 = c1 + 1;
              c2 = c1 + 1;  
              if (input == a)
              {
                  Console.WriteLine("CONGRATZ!!!!.You got that correct in "+c1
                      + "tries");
                  c1 = c2;
  
              }
              else if (input &gt; a)
              {
                  Console.WriteLine("You guessed the number bit too high.try again ");
              }
              else
              {
                  Console.WriteLine("You guessed the number bit too low ");
              };
          } while (c1 != c2);
  </code></pre>
  
  <p>Whenever i remove that <code>do{}</code> part the upper program works fine but as i add it is showed that problem .</p>