#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
template<class T>
using ordered_set = tree<T, null_type, less<T>,
rb_tree_tag, tree_order_statistics_node_update>;
template<class T, class U>
using ordered_map = tree<T, U, less<T>, rb_tree_tag,
tree_order_statistics_node_update>;
#define ll long long
#define ld long double
#define MOD 998244353
#define MAXN 250000
#define SIZE 100
#define pb push_back
ll power(ll a, ll b){
if (b == 0) return 1;
ll res = power(a, b / 2);
if (b % 2 == 1) return res * res % MOD * a % MOD;
return res * res % MOD;
// if (b % 2 == 1) return res * res * a;
// return res * res;
}
int getPar(vector<pair<int, int>> &parents, int a){
if (parents[a].first == a) return a;
return parents[a].first = getPar(parents, parents[a].first);
}
void join(vector<pair<int, int>> &parents, int a, int b){
int parA = getPar(parents, a);
int parB = getPar(parents, b);
if (parA == parB) return;
parents[parA].first = parB;
parents[parB].second = max(parents[parB].second, parents[parA].second);
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin >> n;
vector<pair<int, int>> nums(n + 1);
for (int i = 1; i <= n; i++){
int val;
cin >> val;
nums[i] = {val, i};
}
sort(nums.begin() + 1, nums.end(), greater<pair<int, int>>());
vector<vector<int>> g(n + 1);
for (int i = 1; i < n; i++){
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
stack<pair<int, int>> edges;
map<pair<int, int>, bool> done;
for (int i = 1; i <= n; i++){
for (auto &p : g[nums[i].second]){
if (!done.count({p, nums[i].second})){
done[{nums[i].second, p}] = 1;
done[{p, nums[i].second}] = 1;
edges.push({nums[i].second, p});
// cout << nums[i].second << ", " << p << " YO\n";
}
}
}
// while(!edges.empty()){
// auto [u, v] = edges.top();
// cout << u << " " << v << "\n";
// edges.pop();
// }
ll ans = 0;
vector<pair<int, int>> parents(n + 1);
for (int i = 1; i <= n; i++){
parents[nums[i].second] = {nums[i].second, nums[i].first};
}
while(!edges.empty()){
auto [u, v] = edges.top();
edges.pop();
ans += parents[getPar(parents, u)].second + parents[getPar(parents, v)].second;
join(parents, u, v);
}
cout << ans << "\n";
return 0;
}
