https://www.cnblogs.com/shwee/p/9060226.html#dingzhi10 https://www.cnblogs.com/shwee/p/9084535.html
https://blog.csdn.net/qq_41851959/article/details/82987974 https://www.luogu.org/blog/IowaBattleship/latex-gong-shi-tai-quan
