.data
n:      .word 9				# int n = 9 ;

# register usage
# $t0: fib(i)
# $t1: fib(i+1)
# $t2: temp
# $t3: counter - from n down to zero
        .text
main: 	add     $t0, $0, $zero		# initialize $t0 = 0
	addi    $t1, $zero, 1		# initialize $t1 = 1
	la      $t2, n			# initialize $t2 = &n
	lw      $t3, 0($t2)		# dereference $t3 = *$t2
fib: 	beq     $t3, $0, finish		# while ($t3 != 0) {
	add     $t2,$t1,$t0		#  compute next fib 
	move    $t0, $t1		#  set up for next iteration
	move    $t1, $t2
	subi    $t3, $t3, 1		#  decrement counter
	j       fib  			# }
finish: addi    $a0, $t0, 0		
	li      $v0, 1		# you will be asked about what the purpose of this line for syscall 
	syscall			
	li      $v0, 10		
	syscall