#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MAXN = 100005;
int p[MAXN], rnk[MAXN];
ll larg[MAXN], ans;
vector<int> adj[MAXN];
int root(int x){
if (p[x] == -1) return x;
return p[x] = root(p[x]);
}
void join(int ra, int rb){
if (rnk[ra] > rnk[rb]) swap(ra, rb);
p[ra] = rb;
if (rnk[ra] == rnk[rb]) rnk[rb]++;
ans += larg[ra] + larg[rb];
larg[rb] = max(larg[rb], larg[ra]);
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
int nodes; cin >> nodes;
vector<pair<ll, int>> vec(nodes + 1);
for (int i = 1; i <= nodes; i++){
ll v; cin >> v;
vec[i] = {v, i};
}
sort(vec.begin(), vec.end());
for (int i = 1; i < nodes; i++){
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
vector<bool> in(nodes + 1, 0);
memset(p, -1, sizeof(p));
for (auto &[v, i] : vec){
larg[i] = v;
for (int nn : adj[i])
if (in[nn]){
int ra = root(i), rb = root(nn);
join(ra, rb);
}
in[i] = 1;
}
cout << ans;
}
