永夜莫明的博客

链接：https://ac.nowcoder.com/acm/contest/881/F 来源：牛客网 题目描述 Bobo has a triangle ABC with A(x1,y1),B(x2,y2)and C(x3,y3). Picking a point P uniformly in triangle ABC, he wants to know the expectation v...

题目链接：https://ac.nowcoder.com/acm/contest/882/A 题意：n个点的环，初始在0，可以随机向前向后，n个位置都走完，最后停在m的概率，最后输出前i组概率的乘积 题解：打表发现，1 ~n-1的点概率为，特别情况，n=1，m=0概率为1，其他m=0概率为0 #include<iostream> #include<cstdio> ...

https://cn.vjudge.net/contest/312853#problem/F New Year is coming in Tree World! In this world, as the name implies, there arencities connected byn - 1roads, and for any two distinct cities there ...