#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 7;
int n,val[N],par[N],sz[N],mx[N];
vector < int > tree[N];
vector < pair < int , int > > order;
map < pair < int , int > , bool > vis;
int find(int a){
if(par[a] == a)return a;
return par[a] = find(par[a]);
}
void merge(int a , int b){
a = find(a) , b = find(b);
if(a == b)return;
if(sz[a] > sz[b])swap(a,b);
sz[b] += sz[a];
mx[b] = max(mx[b] , mx[a]);
par[a] = b;
}
void solve(){
iota(par , par + N , 0);
fill(sz , sz + N , 1);
cin >> n;
vector < pair < int , int > > sorted_val(n+1);
for(int i = 1;i<=n;i++){
cin >> val[i];
mx[i] = val[i];
sorted_val[i] = {val[i],i};
}
sort(sorted_val.begin() , sorted_val.end());
reverse(sorted_val.begin() , sorted_val.end());
for(int i = 1;i<n;i++){
int u,v;cin >> u >> v;
tree[u].push_back(v);
tree[v].push_back(u);
}
for(auto itr : sorted_val){
for(auto itr1 : tree[itr.second]){
if(vis[{itr.second,itr1}] == 0){
vis[{itr.second,itr1}] = vis[{itr1,itr.second}] = 1;
order.push_back({itr1,itr.second});
}
}
}
reverse(order.begin() , order.end());
long long ans = 0;
for(auto itr : order){
ans += mx[find(itr.first)] + mx[find(itr.second)];
merge(itr.first , itr.second);
}
cout << ans << endl;
}
signed main(){
ios_base::sync_with_stdio(0);cin.tie(0);
int testcase = 1;//cin >> testcase;
while(testcase--)solve();
}
