#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MAXN = 1e5 + 25;
ll dp[MAXN][101][2], p[MAXN];
vector <int> adj[MAXN];
int n, v;
void fix (int pos, int par) {
if (par) {
adj[pos].erase(find(adj[pos].begin(), adj[pos].end(), par));
}
for (auto j : adj[pos]) {
fix(j, pos);
}
}
ll ans (int pos, int cur, int c) {
ll &ret = dp[pos][cur][c];
if (ret != -1) {
return ret;
}
ll v = (c ? p[pos] : 0);
ret = v;
int z = (int)adj[pos].size();
ll pref[z + 1] = {}, suff[z + 2] = {};
for (int i = 0; i < z; i++) {
pref[i + 1] = pref[i] + p[adj[pos][i]];
}
for (int i = z - 1; i >= 0; i--) {
suff[i + 1] = suff[i + 2] + p[adj[pos][i]];
}
for (int i = 0; i < z; i++) {
ret = max(ret, v + ans(adj[pos][i], cur, 0));
if (cur) ret = max(ret, v + pref[i] + suff[i + 2] + ans(adj[pos][i], cur - 1, 1));
}
return ret;
}
void solve () {
cin >> n >> v;
for (int i = 1; i <= n; i++) {
cin >> p[i];
}
for (int i = 1; i < n; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
memset(dp, -1, sizeof(dp));
fix(1, 0);
cout << ans(1, v, 0) << '\n';
}
signed main () {
ios::sync_with_stdio(0); cin.tie(0);
int tc = 1; //cin >> tc;
while (tc--) solve();
}
