org 0000h

			   mov r3,#20 
			   mov r6,#20
			   mov r1,#30h
	     	   mov 30h,#01
			   mov 31h,#01
			   mov 32h,#01
			   mov 33h,#04
			   mov 34h,#03
			   mov 35h,#03
			   mov 36h,#03
			   mov 37h,#03
			   mov 38h,#03
			   mov 39h,#03
			   mov 3ah,#03
			   mov 3bh,#04
			   mov 3ch,#04
			   mov 3dh,#04
			   mov 3eh,#02
			   mov 3fh,#02
			   mov 40h,#02
			   mov 41h,#01
			   mov 42h,#01
			   mov 43h, #01
			  

			   mov a,r3
			  
			   add a,r1
			   mov r0,a
			   setb PSW.3
			   mov r1,a
			   clr PSW.3
			   CLR 02
			   clr a

	back:	   
	           mov r3,#20
			   CLR  PSW.7
			   MOV   A,03
			   SUBB  A,02
			   MOV   R3,A
			   inc r2
			   CLR  A                                            
			   mov a,@r1
			   jz here
			   mov @r0,a
			   JMP forward

			   mov r1,#30h
		more:  mov r5,#00
			   clr a
			   

	again:     mov a,@r1
	           setb PSW.3
			   xrl a,@r1
			   clr PSW.3
			   jnz there
			   mov @r1,#00
			   inc r5

	there:	   inc r1
	           djnz r3,again
			   clr a
			   mov a,r5
			   inc r0
			   
			   mov @r0,a
			   clr a
			   inc r0
			   mov b,r0
			   setb psw.3
			   mov r1,b
			   clr psw.3

   here:       mov r1,#30h
               mov a,r2
			   add a,r1
			   mov r1,a
			   clr a
			   djnz r6,back	           
			   


    forward :  
	           clr c
               mov r4,#08
               mov r7,#00

	   back1:  clr c
	           rrc a
	           jc again1
			   djnz r4,back1
			   jmp sea

	  again1:  inc r7
	           djnz	r4,back1

	     sea:  mov b,#02
			   mov a,r7
  			   div ab
			   mov a,b
			   inc r0
			  

			   jz here1
			   mov @r0,#01
			   nop
			   nop
			   jmp more
	   here1:  mov@r0 ,#00
	       
	           mov a,r6
			   jnz more
			    
	           end