/* -*- coding: utf-8 -*-
 *
 * 3222.cc:  No.3222 Let the World Forget Me - yukicoder
 */

#include<cstdio>
#include<vector>
#include<set>
#include<queue>
#include<algorithm>
#include<utility>

using namespace std;

/* constant */

const int MAX_N = 100000;

/* typedef */

using ll = long long;
using vi = vector<int>;
using si = set<int>;
using qi = queue<int>;
using pii = pair<int,int>;

/* global variables */

int ps[MAX_N], cs[MAX_N];
si nbrs[MAX_N];
int ds[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  for (int i = 0; i < n; i++) scanf("%d", ps + i);
  for (int i = 1; i < n; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--, v--;
    nbrs[u].insert(v);
    nbrs[v].insert(u);
  }
  for (int i = 0; i < m; i++) scanf("%d", cs + i), cs[i]--;

  fill(ds, ds + n, -1);
  qi q;
  for (int i = 0; i < m; i++) ds[cs[i]] = 0, q.push(cs[i]);

  while (! q.empty()) {
    int u = q.front(); q.pop();
    for (auto v: nbrs[u])
      if (ds[v] < 0) ds[v] = ds[u] + 1, q.push(v);
  }
  //for (int i = 0; i < n; i++) printf(" %d", ds[i]); putchar('\n');

  priority_queue<pii> pq;
  for (int u = 0; u < n; u++)
    if (ds[u] > 0 && nbrs[u].size() == 1) pq.push({ps[u], u});

  ll sum = 0;
  for (int d = 0; ! pq.empty(); d++) {
    while (! pq.empty() && ds[pq.top().second] <= d) pq.pop();
    if (pq.empty()) break;

    auto [p, u] = pq.top(); pq.pop();
    sum += p;

    int up = *(nbrs[u].begin());
    nbrs[up].erase(u);
    if (ds[up] > d && nbrs[up].size() == 1) pq.push({ps[up], up});
  }

  printf("%lld\n", sum);
  
  return 0;
}