#include <iostream>
#include <vector>

#define pb push_back
#define mp make_pair

using namespace std;

typedef long long ll;

const ll INF = 1e17;

int a[100000];
ll ans[100000], sm, sum[100000];
vector <int> g[100000], u;

ll dfs(int v)
{
    ll rew;
    u[v] = 1;
    for(int i = 0; i < g[v].size(); i++)
    {
        int to = g[v][i];
        if(!u[to])
        {
            rew = dfs(to);
            ans[v] = max(ans[v], rew);
            sum[v] += rew;
        }
    }
    u[v] = 2;
    ans[v] = max(ans[v], sm - a[v] - sum[v]);
    return sum[v] + a[v];
}

int main()
{
    int n;
    cin >> n;
    u.resize(n);
    for(int i = 0; i < n; i++)
    {
        cin >> a[i];
        sm += a[i];
    }
    //cout << sm << endl;
    for(int i = 0; i < n - 1; i++)
    {
        int a, b;
        cin >> a >> b;
        a--, b--;
        g[a].pb(b);
        g[b].pb(a);
    }
    ll c = dfs(0);
    ll mn = INF;
    int num;
    for(int i = 0; i < n; i++)
        if(mn > ans[i])
        {
            mn = ans[i];
            num = i;
        }
    cout << num + 1;

    return 0;
}