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```
#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
const int N = 5001 , M = 2001;
int sz[N] , dp[N][M] , val[N];
vector<int> adj[N];
ll sum[N];
const ll mod = (119 << 23) + 1, root = 62; // = 998244353
// For p < 2^30 there is also e.g. 5 << 25, 7 << 26, 479 << 21
// and 483 << 21 (same root). The last two are > 10^9.
ll modpow(ll b, ll e) {
    ll ans = 1;
    for (; e; b = b * b % mod, e /= 2)
        if (e & 1) ans = ans * b % mod;
    return ans;
}
typedef vector<ll> vl;
void ntt(vl &a) {
    int n = sz(a), L = 31 - __builtin_clz(n);
    static vl rt(2, 1);
    for (static int k = 2, s = 2; k < n; k *= 2, s++) {
        rt.resize(n);
        ll z[] = {1, modpow(root, mod >> s)};
        rep(i,k,2*k) rt[i] = rt[i / 2] * z[i & 1] % mod;
    }
    vi rev(n);
    rep(i,0,n) rev[i] = (rev[i / 2] | (i & 1) << L) / 2;
    rep(i,0,n) if (i < rev[i]) swap(a[i], a[rev[i]]);
    for (int k = 1; k < n; k *= 2)
        for (int i = 0; i < n; i += 2 * k) rep(j,0,k) {
            ll z = rt[j + k] * a[i + j + k] % mod, &ai = a[i + j];
            a[i + j + k] = ai - z + (z > ai ? mod : 0);
            ai += (ai + z >= mod ? z - mod : z);
        }
}
vl conv(const vl &a, const vl &b) {
    if (a.empty() || b.empty()) return {};
    int s = sz(a) + sz(b) - 1, B = 32 - __builtin_clz(s),
        n = 1 << B;
    int inv = modpow(n, mod - 2);
    vl L(a), R(b), out(n);
    L.resize(n), R.resize(n);
    ntt(L), ntt(R);
    rep(i,0,n)
        out[-i & (n - 1)] = (ll)L[i] * R[i] % mod * inv % mod;
    ntt(out);
    return {out.begin(), out.begin() + s};
}
void dfs(int u, int p) {
    sz[u] = 1;
    dp[u][val[u]] = 1;
    for (auto &v : adj[u]) if (v != p) {
        dfs(v, u);
        vl dp_u(M, 0), dp_v(M, 0);
        for (int i = 0; i < M; ++i) {
            dp_u[i] = dp[u][i];
            dp_v[i] = dp[v][i];
        }
        vl conv_result = conv(dp_u, dp_v);
        for (int s = 0; s < M; ++s) {
            dp[u][s] = (dp[u][s] + conv_result[s]) % mod;
        }
    }
}
int main(){
    ios::sync_with_stdio(0); cin.tie(NULL); cout.tie(0);
        #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
        freopen("error.txt", "w", stderr);
        #endif 
    int x , n , q; cin >> n >> x >> q;
    --x;
    for(int i = 0; i < n; ++i) cin >> val[i];
    for(int i = 1; i < n; ++i){
        int u , v; cin >> u >> v;
        --u; --v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    dfs(x , x);
    for(int s = 1; s < M; ++s){
        sum[s] += sum[s - 1];
        if(sum[s] >= mod) sum[s] -= mod;
    }
    for(int s = 1; s < M; ++s){
        sum[s] = sum[s - 1] + dp[x][s];
        if(sum[s] >= mod) sum[s] -= mod;
    }
    

    while(q--){
        int l , r; cin >> l >> r;
        ll ans = (sum[r] - sum[l - 1] + mod) % mod;
        cout << ans << '\n';
    }
}
```
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