ld	zero   # initialize sum to zero
	st	sum
loop	get            # read a number
	jz	done   # no more input if number is zero
	add	sum    # add in accumulated sum
	st	sum    # store new value back in sum
	j	loop   # go back and read another number

done	ld	sum    # print sum
	put
	halt

zero	const	0
sum	const