#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cstring>
#include <cassert>
#include <tr1/unordered_map>

using namespace std;
using namespace tr1;

typedef pair<int, int> pi;
typedef long long ll;
typedef long double ld;

const int N = 1e5 + 5;

vector< int > v;
vector< int > adj[N];

unordered_map<int, unordered_map<int, ld> > dp;
unordered_map<int, unordered_map<int, ld> > done;
ld memo[N];


ld solve(int cur, int par){
    if(dp.count(cur) && dp[cur].count(par)){
        return dp[cur][par];
    }
    ld &ret = dp[cur][par];
    ret = v[cur];
    ld tot = 0;
    if(done.count(cur) && done[cur].size() == adj[cur].size()){
        if(par != 0){
            tot = memo[cur] - done[cur][par];
        }else{
            tot = memo[cur];
        }
    }else{
        for(int i = 0; i < adj[cur].size(); i++){
            int to = adj[cur][i];
            if(to == par) continue;
            ld val = solve(to, cur);
            if(done[cur].count(to) == 0){
                done[cur][to] = val;
                memo[cur] += val;
            }
            tot += val;
        }
    }
    if(adj[cur].size() - (par != 0) != 0) tot /= adj[cur].size() - (par != 0);
    ret += tot;
    return ret;
}

int main(){
#ifndef ONLINE_JUDGE
    freopen("in.in", "r", stdin);
    //freopen("out.out", "w", stdout);
#endif
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, x, a, b;
    cin >> n;
    v.push_back(0);
    for(int i = 0; i < n; i++){
        cin >> x;
        v.push_back(x);
    }
    for(int i = 1; i < n; i++){
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }

    ld best = 1e200;
    int ans = -1;
    for(int i = 1; i <= n; i++){
        ld cur = solve(i, 0);
        if(cur < best){
            best = cur;
            ans = i;
        }
    }

    cout << ans << endl;

    return 0;
}