#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
vector<pair<int, int>> edges;
ll hardness[100001], ans = 0;
int cmp[100001];
int find(int A) {
while (cmp[A] != A) cmp[A] = cmp[cmp[A]], A = cmp[A];
return A;
}
void onion(int A, int B) {
A = find(A), B = find(B);
if (A == B) return;
ans += hardness[A] + hardness[B];
hardness[B] = max(hardness[B], hardness[A]);
cmp[A] = B;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
for (int i = 1; i <= n; i++) cin >> hardness[i];
for (int i = 1; i < n; i++) {
int a, b;
cin >> a >> b;
if (hardness[a] < hardness[b]) swap(a, b);
edges.push_back({a, b});
}
sort(edges.begin(), edges.end(), [](pair<int, int> A, pair<int, int> B) { return hardness[A.first] < hardness[B.first]; });
iota(cmp + 1, cmp + n + 1, 1);
for (pair<int, int> i : edges) onion(i.first, i.second);
cout << ans;
return 0;
}
