#include <bits/stdc++.h>

#include "atcoder/modint.hpp"
using mint = atcoder::modint998244353;

#include "testlib.h"

void solve() {
    int n = inf.readInt(2, 5000);
    inf.readEoln();
    std::vector<int> A = inf.readInts(n, -1, n);
    inf.readEoln();
    std::reverse(A.begin(), A.end());

    std::vector<bool> rem(n, false);
    int cc = 0;
    for (int i = 0; i < n; i++) {
        if (A[i] == -1) continue;
        assert(A[i] != 0);
        A[i]--;
        ensuref(!rem[A[i]], "A[%d] is already used", i);
        rem[A[i]] = true;
        cc++;
    }

    std::vector<mint> dp1(n, 0), dp2(n, 0);
    if (A[0] == -1) {
        for (int i = 0; i < n; i++) {
            if (!rem[i]) dp1[i] = 1;
        }
    } else {
        dp1[A[0]] = 1;
        cc--;
        rem[A[0]] = false;
    }

    for (int i = 1; i < n; i++) {
        std::vector<mint> ndp1(n, 0), ndp2(n, 0);
        if (A[i] != -1) {
            int a = A[i];
            for (int j = a + 1; j < n; j++) {
                ndp1[a] += dp1[j] + dp2[j];
            }
            for (int j = 0; j < a; j++) {
                ndp2[j] += dp1[j];
            }
            rem[a] = false;
            cc--;
        } else {
            int c2 = cc;
            for (int j = 0; j < n; j++) {
                if (rem[j]) {
                    c2--;
                    continue;
                }

                int x = n - 1 - j - (i - 1) - c2;
                if (x < 0) continue;
                ndp2[j] += dp1[j] * x;
            }
            mint tot = 0;
            for (int j = n - 1; j >= 0; j--) {
                if (rem[j]) continue;
                ndp1[j] += tot;
                tot += dp1[j] + dp2[j];
            }
        }
        std::swap(dp1, ndp1);
        std::swap(dp2, ndp2);
    }

    mint ans = dp1[0] + dp2[0];
    std::cout << ans.val() << std::endl;
}

int main(int argc, char *argv[]) {
    std::cin.tie(0)->sync_with_stdio(0);
    registerValidation(argc, argv);
    int T = inf.readInt(1, 5000);
    inf.readEoln();
    while (T--) solve();
    inf.readEof();
}