allocate-registers x, one, result, jump

	read x
	li one, 1
	; fall through

even:
	li jump, true
	jeqz x, jump
	sub x, x, one
	; fall through

odd:
	li jump, false
	jeqz x, jump
	sub x, x, one
	li jump, even
	j jump

true:
	li result, 1
	li jump, done
	j jump

false:
	li result, 0
	; fall through

done:
	write result
	halt

test even-case
    >>> 4
    1

test odd-case
    >>> 5
    0

test zero-is-even
    >>> 0
    1

test one-is-odd
    >>> 1
    0