C#算术运算符

using System;
namespace OperatorsAppl {

   class Program { 

      static void Main(string[] args) { 
         int a = 21;
         int b = 10;
         int c;

         c = a + b;
         Console.WriteLine("Line 1 - Value of c is {0}", c);

         c = a - b;
         Console.WriteLine("Line 2 - Value of c is {0}", c);

         c = a * b;
         Console.WriteLine("Line 3 - Value of c is {0}", c);

         c = a / b;
         Console.WriteLine("Line 4 - Value of c is {0}", c);

         c = a % b;
         Console.WriteLine("Line 5 - Value of c is {0}", c);

         c = a++;
         Console.WriteLine("Line 6 - Value of c is {0}", c);

         c = a--;
         Console.WriteLine("Line 7 - Value of c is {0}", c);
         Console.ReadLine();
      }
   }
}