You are given a tree with $N$ vertices (numbered $1$ through $N$) and a sequence of integers $A_1, A_2, \ldots, A_N$. You may choose an arbitrary permutation $p_1, p_2, \ldots, p_N$ of the integers $1$ through $N$. Then, for each vertex $i$, you should assign the value $A_{p_i}$ to this vertex.
The profit of a path between two vertices $u$ and $v$ is the sum of the values assigned to the vertices on that path (including $u$ and $v$).
Let's consider only (undirected) paths that start at a leaf and end at a different leaf. Calculate the maximum possible value of the sum of profits of all such paths. Since this value could be very large, compute it modulo $10^9 + 7$.

-----Input-----
- The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
- The first line of each test case contains a single integer $N$.
- The second line contains $N$ space-separated integers $A_1, A_2, \ldots, A_N$.
- Each of the following $N−1$ lines contains two space-separated integers $u$ and $v$ denoting that vertices $u$ and $v$ are connected by an edge.

-----Output-----
For each test case, print a single line containing one integer — the maximum sum of profits, modulo $10^9 + 7$.

-----Constraints-----
- $1 \le T \le 1,000$
- $1 \le N \le 300,000$
- $1 \le A_i \le 10^9$ for each valid $i$
- the sum of $N$ over all test cases does not exceed $5 \cdot 10^5$

-----Example Input-----
2
4
1 2 3 4
1 2
2 3
2 4
5
1 2 3 4 5
1 2
2 3
3 4
4 5

-----Example Output-----
24
15

-----Explanation-----
Example case 1: $(1, 4, 2, 3)$ is one of the possible permutations that give the optimal answer. Then, the profits of paths between pairs of vertices $(1, 3)$, $(1, 4)$ and $(3, 4)$ are $7$, $8$ and $9$ respectively.
Example case 2: Here, any permutation could be chosen.

见题面

见题面