#include <bits/stdc++.h>
using namespace std;
typedef unsigned int ui;
typedef long long ll;
#define all(x) (x).begin(), (x).end()
const int N = 3e3 + 20, p = 998244353;
vector<int> e[N];
int F[N][N * 2], *f[N], c[N], cnt[N], a[N], siz[N];
int res, tot;
bool ed[N];
void dfs(int u)
{
  f[u][a[u]] = 1;
  siz[u] = 1;
  ed[u] = 1;
  for (int v : e[u])
    if (!ed[v])
    {
      dfs(v);
      static int G[N * 2];
      int *g = G + N;
      copy_n(f[u] - siz[u] - siz[v], (siz[u] + siz[v]) * 2 + 1, g - siz[u] - siz[v]);
      for (int i = -siz[u]; i <= siz[u]; i++)
        for (int j = -siz[v]; j <= siz[v]; j++)
        {
          g[i + j] = (g[i + j] + (ll)f[u][i] * f[v][j]) % p;
        }
      copy_n(g - siz[u] - siz[v], (siz[u] + siz[v]) * 2 + 1, f[u] - siz[u] - siz[v]);
      siz[u] += siz[v];
      siz[u] = min(siz[u], tot);
    }
  for (int i = 1; i <= siz[u]; i++)
    if ((res += f[u][i]) >= p)
      res -= p;
  ed[u] = 0;
}
int main()
{
  ios::sync_with_stdio(0);
  cin.tie(0);
  int n, i, j;
  cin >> n;
  for (i = 1; i <= n; i++)
    cin >> c[i], ++cnt[c[i]];
  for (i = 1; i < n; i++)
  {
    int u, v;
    cin >> u >> v;
    e[u].push_back(v);
    e[v].push_back(u);
  }
  for (i = 1; i <= n; i++)
    f[i] = F[i] + N;
  for (i = 1; i <= n; i++)
    if (cnt[i])
    {
      tot = cnt[i];
      for (j = 1; j <= n; j++)
        fill_n(f[j] - cnt[i], cnt[i] * 2 + 1, 0);
      for (j = 1; j <= n; j++)
        a[j] = c[j] == i ? 1 : -1;
      dfs(1);
      // cerr<<i<<' '<<res<<endl;
    }
  cout << res << endl;
}

function<void(int, int)> dfs = [&](int u, int fa)
{
l[u] = ++ T;
for (int i = h[u]; i != -1; i = ne[i])
{
  int v = e[i];
  tr[T] = W[i];
  if (v == fa) continue;
  dfs(v, u);
}
r[u] = T;
};