#include<bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#define tof_io ios_base::sync_with_stdio(false);cin.tie(0) , cout.tie(0);
#define double long double
#define int long long
#define pb push_back
#define all(x) x.begin(),x.end()
#define endl '\n'
#define sz(x) x.size()
const int mod = 1e9 + 7; //998244353 1e9+7 1e9+9
const int N = 1e6 + 1;
const int lg = 23;
const int inf = 1e18;
int fac[N];
int inv[N];
int cnt[N];
int n ;
vector<int> vc;
vector<pair<int, int> > adj;
int ans = 0;
int dnt_pow (int a, int b, int md = mod){int ans = 1; while(b){if(b&1){ans = (a*ans)%md;}a = (a*a)%md;b >>= 1;}return ans ;}
void dnt_bld (){fac[0] = 1; inv[0] = dnt_pow(fac[0],mod-2) ;for(int i = 1 ; i < N ; i++) {fac[i] = (fac[i-1] * i) % mod;inv[i] = dnt_pow( fac[i] , mod-2);}}
int dnt_ncr (int r,int n){if(r>n) return 0; return fac[n] * inv[r] % mod * inv[n-r] % mod;}
bool cmp (pair<int, int> x, pair<int, int> y){return max(cnt[x.first], cnt[x.second]) < max(cnt[y.first], cnt[y.second]);}
int get(int x){return (vc[x] == x ? x : vc[x] = get(vc[x]));}
void merg(int x, int y)
{
int a = get(x);
int b = get(y);
if (a != b)
{
vc[a] = b;
ans = ans + cnt[a];
ans = ans + cnt[b];
cnt[b] = max(cnt[b], cnt[a]);
}
}
int32_t main()
{
cin >> n;
vc.pb(0);
for (int i = 1; i <= n; i++)
{
cin >> cnt[i];
vc.pb(i);
}
for (int i = 1; i < n; i++)
{
int x, y;
cin >> x >> y;
adj.pb(make_pair(x,y));
}
sort(all(adj), cmp);
for (auto v : adj)
merg(v.first, v.second);
cout << ans;
}
