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

ll x = 0;

struct Graph {
    struct Vertex { int n; int a; };
    struct Edge { int i, n; };
    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 };
        v[a].n = m;
        m++;
    }
    int dfs(int i, int p) {
        int k = 1, k1[2] = {};
        auto f = [&](int i1, int l) {
            if (v[i].a != v[i1].a) {
                k1[v[i].a > v[i1].a] += l;
                x -= (ll)l * l;
            }
        };
        for (int j = v[i].n; j >= 0; j = e[j].n) {
            Edge &o = e[j];
            if (o.i == p) continue;
            int l = dfs(o.i, i);
            k += l;
            f(o.i, l);
        }
        if (p >= 0) f(p, n - k);
        x += (ll)k1[0] * k1[0] + (ll)k1[1] * k1[1];
        return k;
    }
    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.dfs(0, -1);

    cout << x / 2 % 998244353 << endl;

    return 0;
}