题目:https://www.lydsy.com/JudgeOnline/problem.php?id=2878 很好的树上概率题的思路,就是分成up和down. 代码中有众多小细节.让我弃疗好几天的致命小细节是dfs1里面那个sum要定义成double的!…… #include<iostream> #include<cstdio> #include<cstring> #define db double using namespace std; ; int n,m,he…
Network Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 4478 Accepted: 1292 Description Yixght is a manager of the company called SzqNetwork(SN). Now she's very worried because she has just received a bad news which denotes that DxtNet…