shithub: kwa

ref: 6d0ade9e0f10517872304e94c2c5d0e3a14c426d
dir: /test/t.randk/

{
	k = 2
	n = NF
	i = 1
	while ( i <= n ) {
		if ( rand() < k/n ) {
			print i
			k--
		}
		n--
		i++
	}
}