#include <bits/stdc++.h>
#define fast cin.tie(0)->sync_with_stdio(0);
#define int long long
#define inf ((int)1e18)
#define N 100000
using namespace std;
int par[N], mx[N];
vector <vector<int> > adj;
vector <pair<int, int> > arr;
vector <int> val;
int ans = 0;
int parent(int x) {
if(par[x] == x) return x;
par[x] = parent(par[x]);
mx[x] = max(mx[x], mx[par[x]]);
return par[x];
}
void merge(int x, int y) {
x = parent(x);
y = parent(y);
par[y] = x;
ans += mx[y] + mx[x];
mx[x] = max(mx[x], mx[y]);
}
int32_t main(){
fast
int n;
cin >> n;
arr.resize(n);
adj.resize(n);
val.resize(n);
for(int i = 0; i < n; i++) {
cin >> val[i];
arr[i].first = val[i];
arr[i].second = i;
}
sort(arr.begin(), arr.end());
for(int i = 0; i < n - 1; i++) {
int a, b;
cin >> a >> b;
a--, b--;
if(val[a] > val[b] or (val[a] == val[b] and a > b)) {
// önce a çıkartılacak
adj[a].push_back(b);
}
else {
adj[b].push_back(a);
}
}
// pre-calc for dsu
for(int i = 0; i < n; i++) par[i] = i, mx[i] = val[i];
// now do the merging
for(int i = 0; i < n; i++) {
int node = arr[i].second;
for(auto it:adj[node]) {
merge(node, it);
// cout << node << " " << it << " " << ans << "\n";
}
}
cout << ans << "\n";
}
