write a go solution for Description:
You are given a tree with n nodes numbered from 1 to n, along with an array of size n. The value of i-th node is a_i. There are q queries. In each query, you are given 2 nodes numbered as x and y.

Consider the path from the node numbered as x to the node numbered as y. Let the path be represented by x=p_0,p_1,p_2,ldots,p_r=y, where p_i are the intermediate nodes. Compute the sum of a_p_ioplusi for each i such that 0<=i<=r where oplus is the XOR operator.

More formally, compute \sum_{i =0}^{r} a_{p_i}\oplus i.

Input Format:
The first line contains a single integer t (1<=t<=10^4) — the number of test cases. Each test case contains several sets of input data.

The first line of each set of input data contains a single integer n (1<=n<=5*10^5) — the number of nodes.

The next n-1 lines of each set of input data contain 2 integers, u and v representing an edge between the node numbered u and the node numbered v. It is guaranteed that unev and that the edges form a tree.

The next line of each set of input data contains n integers, a_1,a_2,ldots,a_n (1<=a_i<=5*10^5) — values of the nodes.

The next line contains a single integer q (1<=q<=10^5) — the number of queries.

The next q lines describe the queries. The i-th query contains 2 integers x and y (1<=x,y<=n) denoting the starting and the ending node of the path.

It is guaranteed that the sum of n over all test cases does not exceed 5*10^5 and sum of q over all test cases does not exceed 10^5.

Output Format:
For each query, output a single number — the sum from the problem statement.

Note:
None. Output only the code with no comments, explanation, or additional text.