System.out.println("Enter your name:");
     name=sc.next();
    System.out.println("Enter your age:");
     age=sc.nextInt();
     }

 Clerk()
 {
  sal=20000;
  Designation="Clerk";
 }    

public void raiseSal()
 {
    sal=sal+(sal*10)/100;
     System.out.println("sal:"+sal);
     System.out.println("Salary raised by 10%");
      super.sal=sal;
  }
  Now take property of manager and extends employee
  class Manager extends Employee

  Manager()
   {
   sal=50000;
    Designation="Manager";
  }
public void raiseSal()
 {
    sal=sal+(sal*20)/100;
     System.out.println("sal:"+sal);
     System.out.println("Salary raised by 20%");
        super.sal=sal;
  }
  Similary programmer side extends Employee
  rogrammer()
  {
    sal=100000;
    Designation="Programmer";
  }

public void raiseSal()
 {
    sal=sal+(sal*25)/100;
     System.out.println("sal:"+sal);
     System.out.println("Salary raised by 25%");
     super.sal=sal;
  }
  In service -in use do while and switch statement
    do

 System.out.println("\n 1.create\n 2.Display\n 3.Raise Sal\n 4.Exit\n Enter choice");

 choice=sc.nextInt();
    
    
     
    
switch(choice)
 {
 case 1:   do{
            System.out.println("\n 1.Clerk \n 2.Manager \n 3.Programmer\n 4.Exit\n choose");
            d=sc.nextInt();
          
          switch(d)
            {
           case 1:     
                        Clerk f=new Clerk();
                        f.create();
                        c[i]=(Clerk)f;
                        i++;
                         
                     break;
                       
            case 2:    
                        Manager m=new Manager();
		    m.create();
                        c[i]=(Manager)m; 	
	            i++;
                        count++;
                        break;      
                
             case 3:
                     
                     Programmer p=new Programmer();
                      p.create();
                      c[i]=(Programmer)p;
                       i++;
                        
                      break;
                       
               case 4:
                System.out.println("exiting----");
               }   
           }while(d!=4);
            break;
                    
 case 2:   try
             {
               int j=0;
              while(c[j]!=null)
               {
                c[j].display();                  
                j++;
               } 
            }
         catch(NullPointerException ne)
          {
         System.out.println("no records");
         }
         break;
         
 case 3:try
          { 
              int j=0;
               do
               {
              c[j].raiseSal();
               j++;
                }while(c[j]!=null);
               
           }
         catch(NullPointerException ne)
           {
          System.out.println("no records");
           }
           break;
         
 case 4:System.out.println("exiting..");
 default:System.out.println("Invalid choice");
 }