#nullable enable

#region
var _input = Array.Empty<string>();
var _iter = 0;
string String()
{
    while (_iter >= _input.Length) (_input, _iter) = (Console.ReadLine()!.Split(' '), 0);
    return _input[_iter++];
}
T I<T>() where T : IParsable<T> => T.Parse(String(), null);
#endregion

T[] Range<T>(int n, Func<T> F) => Enumerable.Range(0, n).Select(_ => F()).ToArray();

var n = I<int>();
var m = I<int>();
var pz = Range(n, I<int>);
var adjl = Range(n, () => new HashSet<int>());
for (var i = 1; i < n; i++)
{
    var u = I<int>() - 1;
    var v = I<int>() - 1;
    adjl[u].Add(v);
    adjl[v].Add(u);
}
var dz = new int[n];
{
    dz.AsSpan().Fill(int.MaxValue);
    var dq = new Queue<int>();
    for (var i = 0; i < m; i++)
    {
        var c = I<int>() - 1;
        dq.Enqueue(c);
        dz[c] = 0;
    }
    while (dq.Count > 0)
    {
        var v = dq.Dequeue();
        var adjz = adjl[v];
        var nv = dz[v] + 1;
        foreach (var next in adjz) if (dz[next] > nv)
        {
            dz[next] = nv;
            dq.Enqueue(next);
        }
    }
}
var ans = 0L;
var leaves = new PriorityQueue<int, int>();
for (var i = 0; i < n; i++) if (adjl[i].Count == 1) leaves.Enqueue(i, -pz[i]);
for (var t = 1; t <= n; t++)
{
    while (leaves.Count > 0)
    {
        var leaf = leaves.Dequeue();
        if (dz[leaf] < t) continue;
        ans += pz[leaf];
        var ntl = adjl[leaf].First();
        adjl[ntl].Remove(leaf);
        if (adjl[ntl].Count == 1) leaves.Enqueue(ntl, -pz[ntl]);
        break;
    }
}
Console.WriteLine(ans);