n=4的一些解决方案:
..0..0..1..1. .0..1..2..0. .0..0..1..1. .0..1..2..2. .0..0..0..1
..1..2..0..0. .2..0..1..1. .2..2..2..0. .2..0..0..1. .2..2..2..0
..0..1..1..2. .1..2..2..0. .0..1..1..2. .1..1..2..0. .0..1..1..2
..2..2..0..1. .0..1..1..2. .2..0..0..1. .0..0..1..2. .2..0..0..1
..1..1..2..2. .2..2..0..1. .1..2..2..2. .2..2..0..0. .1..2..2..0
..0..0..1..1. .1..1..2..0. .0..1..1..1. .1..1..2..2. .0..0..1..2
..2..2..0..0. .0..0..1..1. .2..2..0..0. .0..0..1..1. .2..2..0..1