5. Three ants, Xiaohong, Xiahei, and Xiaohuang, go on a trip. The hotel has 9 different rooms, and no two ants can stay in rooms that are in the same row or the same column. There are possible arrangements for their rooms.
Problem 440
5. Three ants, Xiaohong, Xiahei, and Xiaohuang, go on a trip. The hotel has 9 different rooms, and no two ants can stay in rooms that are in the same row or the same column. There are possible arrangements for their rooms.