;Salwa Fayyad 

 AREA RESET,DATA ,READONLY
	EXPORT __Vectors;DEFINITION
 
__Vectors DCD 0X20001000
		  DCD Reset_Handler
			  
X EQU 0XA ; define x =10

		ALIGN	
Num DCB  7,4,6,5,1,5,9,2,3,2 ; the number
			
    AREA MYCODE,CODE,READONLY

  ENTRY
    EXPORT Reset_Handler
	  
Reset_Handler	  
    
  LDR R0,=Num
	MOV R1,#10; the index
	MOV R9,#0; sum
loopCount	
    LDRB R2,[R0]; ldrb each number
	CMP R2,#0; compare if the number is ended
	BEQ countDone ; chexk if the number is end
	MUL R3,R2,R1 ; multiply the number and their index
	ADD R9,R3; the sum of the equation
	SUB R1,#1 ;decrease the index 
	ADD R0,R0,#1 ; increment index to the next number
	CMP R1,#1 ; we want index to 2
	BEQ countDone ; branch if equal
	B loopCount; loop ending
countDone

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;; to find the firsh index
    LDR R4,=Num
	MOV R5,#10
loop
    LDRB R8,[R4]
	CMP R8,#0
	BEQ count
	SUB R5,#1
	ADD R4,R4,#1
	CMP R5,#0
	BEQ count
	B loop
count
;;;;; R8 is the first index
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
	;;;;;;;;;; divide the number by 11 
	
    MOV R11,#11 
    MOV R6,#0 
L1 
    CMP R9,R11 ; compare if the sum less than 11
    BLO F      
    SUB R9 ,R9,R11  ; sum the sum 11
    ADD R6,R6,#1   
	MOV R10 ,#11   ; R10=11
    SUB R10,R9     ; sub the mod result by 11 
    B L1  
F	CMP R8,R10     ; compare check sum , if the first index equal the result or not
	BEQ check      ; Branch if equal
	MOV R7,#0      ; if false set R7 =0
	B FINISH       ;end the program
check	
    MOV R7 ,#1    ; if true set R7=1
  
FINISH B FINISH   ; end the program
  END