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There are N cities numbered from 1 to N and N-1 roads connecting these N cities, or consider it is a tree with N nodes. Each road takes 1 day to travel through. There are K people initially stays at different K cities. They decide to meet at the same city as soon as possible. Please find the minimal time needed.

The first line will be an integer \(T (1 \leq T \leq 10)\), which is the number of test cases.

For each test data:

The first line contains two integers \(N (1 \leq N \leq 10^5)\) and \(K (1 \leq K \leq N)\) — the number of cities and the number of friends.

The next N - 1 lines contain two integers A and B, which means there is a road between city A and city B.

Then the next one line contains K integers, the i-th integer \(p_i\) indicates the place they initially stay.

For each test data:

The first line contains two integers \(N (1 \leq N \leq 10^5)\) and \(K (1 \leq K \leq N)\) — the number of cities and the number of friends.

The next N - 1 lines contain two integers A and B, which means there is a road between city A and city B.

Then the next one line contains K integers, the i-th integer \(p_i\) indicates the place they initially stay.

For each case, contains one line, print the minimal time.

```
1
4 2
1 2
2 4
2 3
1 3
```

`1`