Weak Pair

http://acm.hdu.edu.cn/showproblem.php?pid=5877

Problem Description

You are given a rooted tree of $N$ nodes, labeled from 1 to $N$. To the ith node a non-negative value ai is assigned.An ordered pair of nodes $(u,v)$ is said to be weak if
(1) $u$ is an ancestor of $v$ (Note: In this problem a node $u$ is not considered an ancestor of itself);
(2) ${a_u×a_v}\leq{k}$.

Can you find the number of weak pairs in the tree?

Input

There are multiple cases in the data set.
The first line of input contains an integer $T$ denoting number of test cases.
For each case, the first line contains two space-separated integers, $N$ and $k$, respectively.
The second line contains $N$ space-separated integers, denoting $a_1$ to $a_N$.
Each of the subsequent lines contains two space-separated integers defining an edge connecting nodes $u$ and $v$ , where node $u$ is the parent of node $v$.

Constrains:

$1≤N≤10^{5}$

$0≤a_i≤10^{9}$

$0≤k≤10^{18}$

Output

For each test case, print a single integer on a single line denoting the number of weak pairs in the tree.

Sample Input

1
2 3
1 2
1 2

Sample Output

1

题目：

给你一棵有$N$个节点的树,并且每个节点有对应的一个值，现在定义一个叫WEAK PAIR的东西(u,v),当满足一下条件是(u,v)就是WEAK PAIR：
1.u是v的祖先
2.