#include <bits/stdc++.h>
#define int long long
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
using namespace std;
int v;
vector<int> p;
vector<int> np;
vector<vector<int>> neigh;
vector<vector<int>> dpu;
vector<vector<int>> dpd;
int ans=0;
void dfs(int x, int _p){
for (auto u : neigh[x])
{
if(u==_p) continue;
dfs(u,x);
for (int j = 0; j <= v; j++)
{
dpu[x][j]=max(dpu[u][j], dpu[x][j]);
if(j>0) dpu[x][j]=max(dpu[x][j],dpu[u][j-1]+np[x]-p[u]);
dpd[x][j]=max(dpd[u][j],dpd[x][j]);
if(_p>=0&&j>0) dpd[x][j]=max(dpd[u][j-1]+np[x]-p[_p],dpd[x][j]);
else if(j>0) dpd[x][j]=max(dpd[u][j-1]+np[x],dpd[x][j]);
}
}
for (int j = 1; j <= v; j++) dpu[x][j]=max(np[x],dpu[x][j]);
for (int j = 1; j <= v; j++) {
if(_p>=0) dpd[x][j]=max(np[x]-p[_p],dpd[x][j]);
else dpd[x][j]=max(np[x],dpd[x][j]);
}
}
void calc(int x, int _p){
vector<pair<pair<int,int>,pair<int,int>>> up(v+1, {{0,-1},{0,-1}});
vector<pair<pair<int,int>,pair<int,int>>> up2(v+1, {{0,-1},{0,-1}});
for (auto u : neigh[x])
{
if(u==_p) continue;
calc(u,x);
for (int j = 0; j <= v; j++)
{
if(dpu[u][j]>up[j].first.first) up[j]={{dpu[u][j],u},up[j].first};
else if(dpu[u][j]>up[j].second.first) up[j].second={dpu[u][j],u};
if(dpu[u][j]-p[u]>up2[j].first.first) up2[j]={{dpu[u][j]-p[u],u},up2[j].first};
else if(dpu[u][j]-p[u]>up2[j].second.first) up2[j].second={dpu[u][j]-p[u],u};
}
}
for (auto u : neigh[x])
{
if(u==_p) continue;
for (int j = 0; j <= v; j++)
{
int x1=up[v-j].first.first;
if(up[v-j].first.second==u) x1=up[v-j].second.first;
ans=max(ans,x1+dpd[u][j]);
if(j==v) continue;
x1=up2[v-j-1].first.first;
if(up2[v-j-1].first.second==u) {
if(up2[v-j-1].second.second==-1) {x1=-1e9; continue; }
x1=up2[v-j-1].second.first;
}
ans=max(ans,x1+dpd[u][j]+np[x]);
}
}
ans=max(ans,max(dpd[x][v],dpu[x][v]));
}
signed main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
int n; cin >> n >> v;
p.resize(n); neigh.resize(n); np.resize(n,0);
dpu.resize(n,vector<int>(v+1, 0));
dpd.resize(n,vector<int>(v+1, 0));
for (int i = 0; i < n; i++) cin >> p[i];
for (int i = 0; i < n-1; i++)
{
int a,b; cin >> a >> b;
neigh[a-1].push_back(b-1);
neigh[b-1].push_back(a-1);
np[a-1]+=p[b-1];
np[b-1]+=p[a-1];
}
dfs(0,-1);
calc(0,-1);
cout << ans << "\n";
return 0;
}
