#include <bits/stdc++.h>
using std::vector;
using std::array;
using std::pair;
using std::tuple;
struct UnionFind {
vector<int> par;
UnionFind(const int n) : par(n, -1) {}
int find(const int u) {
return par[u] < 0 ? u : par[u] = find(par[u]);
}
int merge(int x, int y) {
x = find(x), y = find(y);
if (x == y) return x;
if (par[x] > par[y]) std::swap(x, y);
par[x] += par[y];
par[y] = x;
return x;
}
};
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
int N;
std::cin >> N;
vector<int> C(N);
for (auto& x : C) {
std::cin >> x;
}
vector<tuple<int, int, int>> edge(N - 1);
for (auto& [c, x, y] : edge) {
std::cin >> x >> y;
x -= 1, y -= 1;
c = std::max(C[x], C[y]);
}
std::sort(edge.begin(), edge.end());
UnionFind dsu(N);
long long ans = 0;
for (auto& [c, x, y] : edge) {
x = dsu.find(x), y = dsu.find(y);
ans += C[x] + C[y];
const int z = dsu.merge(x, y);
C[z] = std::max(C[x], C[y]);
}
std::cout << ans << '\n';
return 0;
}
