Tree paths sum

You are given a weighted tree with $N$ nodes, rooted at node $R$. The nodes are numbered from 1 to $N$. There are $Q$ queries of the form ($U$, $V$), and you should output the sum of the weights on all the edges on the shortest path from node $U$ to $V$. ###Input: - The first line contains $T -$ Number of test cases in a file. - The first line of each test case has $3$ integers $-$ $N$ $Q$