#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
template <class T>
using MaxHeap = std::priority_queue<T>;
template <class T>
using MinHeap = std::priority_queue<T, vector<T>, greater<T>>;
#define rep2(i, n) for (ll i = 0; i < (n); i++)
#define rep3(i, l, r) for (ll i = (l); i < (r); i++)
#define rrep2(i, n) for (ll i = n; i-- > 0;)
#define rrep3(i, r, l) for (ll i = (r); i-- > (l);)
#define overload(a, b, c, d, ...) d
#define rep(...) overload(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define rrep(...) overload(__VA_ARGS__, rrep3, rrep2)(__VA_ARGS__)
#define all(x) begin(x), end(x)
bool chmin(auto& lhs, auto rhs) {
    return lhs > rhs ? lhs = rhs, 1 : 0;
}
bool chmax(auto& lhs, auto rhs) {
    return lhs < rhs ? lhs = rhs, 1 : 0;
}
struct IOIO {
    IOIO() {
        std::cin.tie(0)->sync_with_stdio(0);
    }
} ioio;

void solve() {
    int n, m;
    cin >> n >> m;
    vector<ll> p(n);
    rep(i, n) cin >> p[i];
    vector graph(n, set<int>());
    rep(i, n - 1) {
        int u, v;
        cin >> u >> v;
        u--;
        v--;
        graph[u].insert(v);
        graph[v].insert(u);
    }
    vector<int> c(m);
    rep(i, m) cin >> c[i], c[i]--;

    vector<int> ids(n);
    iota(all(ids), 0);
    sort(all(ids), [&](auto l, auto r) { return p[l] > p[r]; });

    vector<int> cur = c;
    vector<bool> already(n);
    for (auto v: c) already[v] = true;

    ll ans = 0;
    int ids_i = 0;
    while (true) {
        for (; ids_i < n; ids_i++) {
            int i = ids[ids_i];
            if (already[i]) continue;
            if (ssize(graph[i]) != 1) continue;
            int v = *graph[i].begin();
            ans += p[i];
            ids_i++;
            graph[i].erase(v);
            graph[v].erase(i);
            break;
        }
        if (ids_i == n) break;
        vector<int> nxt;
        for (auto u: cur) {
            for (auto v: graph[u]) {
                if (already[v]) continue;
                already[v] = true;
                nxt.push_back(v);
            }
        }
        cur = std::move(nxt);
    }
    cout << ans << '\n';
}

int main() {
    int t = 1;
    //  cin >> t;
    while (t--) solve();
}