sum gosub test B.txt 2018-02-07 adopted for BRUN from (flawed):
yes this is dumb way to SUM, just testing gosub
[
	? n Enter some number to get sum of all pos integers to it, 0 quits
	i n >= 1
		gs SUM
	e
		x
	f
	. The sum is s
	.
]
. This ends the sum gosub test.
s SUM
	n s 1
	n i 1
	[
		n i i + 1
		i i <= n
			n s s + i
		e
			x
		f
	]
r
