IDrandom的专栏

495. Kids and PrizesTime limit per test: 0.5 second(s)Memory limit: 262144 kilobytesinput: standardoutput: standardICPC (International Cardboard Producing Company) is in the bu

D. Bag of micetime limit per test2 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputThe dragon and the princess are arguing abou

FootballTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 3340 Accepted: 1713DescriptionConsider a single-elimination football tournament involving 2n t

概率dp是一类求期望/概率的题目简单总结一下做法对于求期望1.先将状态定义出来2.然后对于每一个状态uuu，考虑他可能的下一个状态vvv，于是从uuu到vvv连一条概率为puvp_{uv}puv​的边。于是写出一个方程dp[u]=(∑dp[v]∗p[u][v])+1dp[u]=(\sum{dp[v]*p[u][v]})+1dp[u]=(∑dp[v]∗p[u][v])+1假如这是...