n=4的一些解决方案:
..3....0....1....0....1....1....0....0....0....1....0....3....1....0....1....3
..2....1....4....0....0....0....3....2....2....0....0....1....3....2....3....1
..1....3....0....1....0....1....0....0....0....1....4....0....1....2....2....0
..0....1....0....1....4....2....1....0....2....1....0....0....1....2....0....4
..0....1....3....0....1....0....2....0....0....0....0....1....0....1....0....0
..3....0....0....0....1....2....1....1....1....2....2....4....2....0....0....3
..2....1....0....1....1....0....0....4....1....0....2....2....0....0....1....1
..1....4....3....2....0....1....0....3....4....3....3....1....1....3....1....0