shithub: kwa

ref: 10e72d182aad860492f6ec2e80b0c05a4dc20b7a
dir: /test/t.randk/

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