3 人解决,5 人已尝试。
4 份提交通过,共有 7 份提交。
8.0 EMB 奖励。
单点时限: 2.0 sec
内存限制: 512 MB
XY_cpp has a tree with $n$ vertices, and each edge has a value. $\textcolor{black}{\rm{t}}\textcolor{red}{\rm{arjen}}$ wants to push XY_cpp $q$ times. Each time he will give XY_cpp a number $m$, and then selects $k$ vertices from the tree. He wants XY_cpp to tell him how many pairs of vertices are Good in the given vertices.
For pair $(u,v)$, we call it Good if the $\gcd$(great common divisor) of all the values on the simple path from $u$ to $v$ is less than or equal to $m$.
Howerver, XY_cpp is too vegetable. All he can do is keeping silent under $\textcolor{black}{\rm{t}}\textcolor{red}{\rm{arjen}}$‘s pushing.
Could you please help pool little xy?
The first line contains one integer $n\ (1\le n\le10^5)$, the number of vertices in the tree.
Each of the next $n-1$ lines contains three integers $u,v,w\ (1\le u,v\le n,u\neq v,1\le w\le10^5)$, denoting that there is an edge with value $w$ between vertices $u$ and $v$
the next line contains one integer $q\ (1\le q\le 10^5)$, denoting the number of the queries.
Each query has two lines.
The first line contains two integers $m\ (1\le m \le 10^5)$ and $k\ (\sum k\le 10^5)$, denoting the given number and the number of selected vertices.
The second line contains $k$ distinct integers, denoting the chosen vertices.
$q$ lines, each line has one integer.
The $i$th line denots the answer to the $i$th query.
5 4 1 2 5 1 5 3 1 5 2 5 3 2 3 3 5 2 1 3 2 5 3
2 0
10 10 1 3 7 1 4 9 7 3 5 1 4 2 7 10 4 9 9 8 2 9 3 8 6 6 8 7 2 5 3 6 7 3 9 7 6 9 10 7 4 3 2
3 20
The tree in sample $1$ is shown in picture.
For query $1$: $m=3$, $k=3$. Vertices $1,2,5$ are selected. For $\rm{pair}(1,2)$, the value on their simple road are $3,5$, so their $\gcd$ is $1$. Similarly, the answer to $\rm{pair}(1,5)$ is $5$, the answer to $\rm{pair}(2,5)$ is $3$. So $\rm{pair}(1,2)$, $\rm{pair}(2,5)$ are called Good.
For query $2$: $m=3$, $k=2$. Vertices $3,5$ are selected. The values on their simple path are all $5$, so the answer to $\rm{pair}(3,5)$ is $5$, which is greater than $m$. Hence, no vertice is called good.
3 人解决,5 人已尝试。
4 份提交通过,共有 7 份提交。
8.0 EMB 奖励。
创建: 2 年前.
修改: 2 年前.
最后提交: 11 月,3 周前.
来源: N/A