摘要:
"Luogu P4122 [USACO17DEC]Blocked Billboard" 解析 + 画图想一想,莫得想复杂咯! Code cpp include include include include include define LL long long using namespace st 阅读全文
摘要:
"Luogu P2181 对角线" 解析 + 法一:每 4 个顶点会有一个交点,答案为 $ C_n^4 $ + 法二:递推做差找规律 Code 法一 法二 cpp include include include include include define LL long long using na 阅读全文