#include <bits/stdc++.h>
#define SPED \
ios_base::sync_with_stdio(false); \
cin.tie(0); \
cout.tie(0);
#define endl "\n"
#define fi first
#define se second
#define lint long long
#define fami signed
#define lore main
#define freefire freopen
const lint INF = 0x1f1f1f1f1f1f1f1f;
const lint NEG = 0xE1E1E1E1E1E1E1E1;
using namespace std;
int n;
lint a[100005];
pair<int, int> edges[100005];
struct Dsu
{
int par[100005], sz[100005];
lint maxi[100005];
void setup()
{
for (int i = 1; i <= n; i++)
{
sz[i] = 1;
par[i] = i;
maxi[i] = a[i];
}
}
int find_par(int now)
{
return par[now] == now ? now : par[now] = find_par(par[now]);
}
void combine(int l, int r)
{
l = find_par(l);
r = find_par(r);
if (l == r)
return;
if (sz[l] < sz[r])
swap(l, r);
par[r] = l;
sz[l] += sz[r];
maxi[l] = max(maxi[l], maxi[r]);
}
} dsu;
bool cmp(pair<int, int> jack, pair<int, int> mck)
{
return max(a[jack.fi], a[jack.se]) < max(a[mck.fi], a[mck.se]);
}
fami lore()
{
SPED;
cin >> n;
for (int i = 1; i <= n; i++)
cin >> a[i];
for (int i = 1; i < n; i++)
{
int l, r;
cin >> l >> r;
edges[i] = {l, r};
}
dsu.setup();
sort(edges + 1, edges + n, cmp);
lint res = 0;
for (int i = 1; i < n; i++)
{
auto [u, v] = edges[i];
u = dsu.find_par(u);
v = dsu.find_par(v);
// if (u == v)
// continue;
res += dsu.maxi[u] + dsu.maxi[v];
dsu.combine(u, v);
}
cout << res;
}
// Let your soul wander where dreams are born.
