#include <bits/stdc++.h>
using namespace std;
using ll = long long;

struct Graph {
    struct Vertex { int n; int a; };
    struct Edge { int i, n; int k; };
    Graph(int n, int m) : v(n, { -1, 0 }), e(m), n(n), m(0) {}
    void add_edge(int a, int b) {
        e[m] = { b, v[a].n, 0 };
        v[a].n = m;
        m++;
    }
    int dfs(int i, int p) {
        int k = 1;
        int j1 = -1;
        for (int j = v[i].n; j >= 0; j = e[j].n) {
            Edge &o = e[j];
            if (o.i == p) {
                j1 = j;
                continue;
            }
            int l = dfs(o.i, i);
            k += l;
            o.k = l;
            //cout << i + 1 << ' ' << o.i + 1 << ' ' << l << endl;
        }
        if (j1 >= 0) {
            e[j1].k = n - k;
            //cout << i + 1 << ' ' << p + 1 << ' ' << n - k << endl;
        }
        return k;
    }
    void solve() {
        dfs(0, -1);

        ll x = 0;
        for (int i = 0; i < n; i++) {
            //ll y = x;
            int k[2] = {};
            for (int j = v[i].n; j >= 0; j = e[j].n) {
                Edge &o = e[j];
                if (v[i].a == v[o.i].a) continue;
                int t = v[i].a > v[o.i].a;
                k[t] += o.k;
            }
            for (int j = v[i].n; j >= 0; j = e[j].n) {
                Edge &o = e[j];
                if (v[i].a == v[o.i].a) continue;
                int t = v[i].a > v[o.i].a;
                //cout << i + 1 << ' ' << o.i + 1 << ' ' << o.k << ' ' << (k[t] - o.k) << endl;
                x += (ll)(k[t] - o.k) * o.k;
            }
            //cout << i + 1 << ' ' << x - y << endl;
        }
        cout << x / 2 % 998244353 << endl;
    }
    vector<Vertex> v;
    vector<Edge> e;
    int n, m;
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;

    Graph g(n, (n - 1) * 2);
    for (int j = 0; j < n - 1; j++) {
        int u, v;
        cin >> u >> v;
        u--; v--;

        g.add_edge(u, v);
        g.add_edge(v, u);
    }
    for (int i = 0; i < n; i++) {
        cin >> g.v[i].a;
    }
    g.solve();

    return 0;
}