C# is

C# is a set of data type.

class numbers
{
     public int a = 1;
     public int b = 2;
}

class changeValue
{
 
   numbers  numb = new numbers();      // declare field of object and initialize it on memory

   public numb.a = 3;   // call a in number class to change its value.
   public numb.b = 5;   // call b in number class to change its value.

}

 
class output
{

 int a = changeValue.numb.a;
 Console.write( a );

}