Display Uppercase and Lowercase letters (Use of OR operator) :

This program displays uppercase and lowercase letters together. 

class Program

{
  static void Main(string[] args)
  {
   char ch;
   for(int i=0;i<26;i++)
   {
    ch = (char) ('A' + i);
    Console.Write(ch);

    ch = (char) (ch | 32);   //ch is now lowercase
    Console.Write(ch+" ");
   }
   Console.Read();
 }
}

OUTPUT: 

Now if we run this program then we can see this ,