#include <bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
using namespace std;
const int MAX=100005;
int N=5;
//vector<int> adj[MAX]={{1},{0,2},{1,3},{2,4},{3}};
vector<int> adj[MAX];
int A[MAX]={3,1,4,1,5};
bool vis[MAX];
int P[MAX];
set<int> C[MAX];
int root=-1;
/*
5
5 2 3 1 4
2 1
3 1
2 4
2 5
*/
void dfs_tree(int i,int p){
int x=p;
int prevx=-1;
while (x!=-1&&A[x]<=A[i]) prevx=x, x=P[x];
if (x==-1){
if (root!=-1){
C[i].insert(root);
P[root]=i;
}
root=i;
P[i]=-1;
}else{
P[i]=x;
C[x].insert(i);
if (prevx!=-1){
C[x].erase(prevx);
C[i].insert(prevx);
P[prevx]=i;
}
}
for (auto v:adj[i]){
if (v==p) continue;
dfs_tree(v,i);
}
}
ll calc(int i){
ll ans=0;
vis[i]=true;
for (auto x:C[i]){
if (vis[x]) continue;
ans+=A[i]+A[x];
//cout<<i<<' '<<x<<'\n';
auto y=calc(x);
ans+=y;;
}
return ans;
}
int main(){
//*
cin>>N;
for (int i=0;i<N;i++) cin>>A[i];
for (int i=0;i<N-1;i++){
int a,b;
cin>>a>>b;
a--,b--;
adj[a].push_back(b);
adj[b].push_back(a);
}
/**/
dfs_tree(0,-1);
//for (int i=0;i<N;i++) cout<<i<<' '<<P[i]<<'\n';
cout<<calc(root);
}
