摘要:
第一次写容斥定理,完全不懂啊,,,弱爆了。。。。。话说这道题最后就是判断横坐标和纵坐标两个值是否互质,如果互质则可以看到,否则看不到。题目:Visible TreesTime Limit: 2000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 593Accepted Submission(s): 225Problem DescriptionThere are many trees forming a m * n grid, the grid starts from... 阅读全文