shithub: trueawk

ref: 2bab10b60b3f4d3bbefdcb60410655f317d1a452
dir: /testdir/t.randk/

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