#include <bits/stdc++.h>
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")

#define int long long
#define ld long double
#define vec vector
#define all(m) (m).begin(), (m).end()
#define forn(i,n) for(int i=0;i<(n);i++)

// TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
using namespace std;

int mod = 1e9+7;
vec<int> a;

bool comp(int i, int j) {
    return a[i] < a[j];
}

vec<int> p;
int fnd(int v) {
    if (v==p[v])
        return v;
    return p[v] = fnd(p[v]);
}
vec<vec<int>> g;
int n;

vec<int> cnt;
vec<int> sumh;

void dfs(int v) {
    cnt[v] = 1;
    sumh[v] = 0;
    for (int u: g[v]) {
        dfs(u);
        cnt[v] += cnt[u];
        sumh[v] += sumh[u]+cnt[u];
        cnt[v] %= mod;
        sumh[v] %= mod;
    }
}


int ans = 0;
void calc(int v) {
    for (int u: g[v]) {
        ans += ((a[v]*((sumh[u]+cnt[u])%mod)%mod)*((cnt[v]-cnt[u])%mod))%mod;
        ans %= mod;
        calc(u);
    }
}

void solve() {
    cin>>n;
    a.resize(n);
    forn(i,n)
        cin>>a[i];
    vec<int> vs(n);
    forn(i,n)
        vs[i] = i;
    sort(all(vs), comp);
    vec<vec<int>> g1(n);
    forn(i,n-1) {
        int a,b;
        cin>>a>>b;
        a--;b--;
        g1[a].push_back(b);
        g1[b].push_back(a);
    }
    p.resize(n);
    forn(i,n)
        p[i] = i;

    g.resize(n);
    vec<int> used(n,false);

    for (int v: vs) {
        for (int u: g1[v]) {
            if (used[u]) {
                int root = fnd(u);
                p[root] = v;
                g[v].push_back(root);
            }
        }
        used[v] = true;
    }

    int root = vs.back();
    cnt.assign(n,0);
    sumh.assign(n,0);
    dfs(root);
    calc(root);

    cout<<ans<<'\n';
}

signed main() {

    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int tt = 1;
    // cin>>tt;
    while (tt--)
        solve();
    return 0;
}