#include <bits/stdc++.h>

using i64 = long long;

#include "atcoder/modint"
using Fp = atcoder::modint998244353;

int main() {
    int N; std::cin >> N;
    std::string S; std::cin >> S;
    std::vector<int> zero_ids;
    for (int i = 0; i < N; ++i) if (S[i] == '0') zero_ids.push_back(i);
    std::vector dp(N, std::vector(N, Fp(0)));
    std::vector is_seen(N, std::vector(N, false));

    auto solve = [&](auto &&self, const int l, const int r) -> Fp {
        if (r - l + 1 < 3) return 0;
        if (is_seen[l][r]) return dp[l][r];
        is_seen[l][r] = true;
        if (S[l] == '1' or S[r] == '1') return dp[l][r] = 0;
        if (S[l + 1] == '0' and S[r - 1] == '0') return dp[l][r] = 0;

        Fp res = 0;
        for (int nl = l + 1; nl != r; ++nl) {
            if (S[nl] != '1') for (int nr = r - 1; nr != nl; --nr) {
                if ((nl != l + 1 or nr != r - 1) and S[nr] != '1') res += self(self, nl, nr);
                if (S[nr] == '0') break;
            }
            if (S[nl] == '0') break;
        }
        const auto itr = std::lower_bound(zero_ids.begin(), zero_ids.end(), l + 1);
        if (itr == zero_ids.end() or *itr >= r) ++res;
        return dp[l][r] = res;
    };

    for (int i = 0; i < N; ++i) for (int j = i; j < N; ++j) solve(solve, i, j);
    std::vector<Fp> dp2_a(N + 1, Fp(0)), dp2_b(N + 1, Fp(0));
    dp2_a[0] = 1;
    for (int i = 0; i < N; ++i) {
        const auto itr = std::lower_bound(zero_ids.begin(), zero_ids.end(), i);
        for (int j = i + 1; j <= N; ++j) {
            dp2_a[j] += (dp2_a[i] + dp2_b[i]) * dp[i][j - 1];
            if (itr == zero_ids.end() or *itr >= j) dp2_b[j] += dp2_a[i];
        }
    }
    std::cout << (dp2_a[N] + dp2_b[N]).val() << std::endl;
    // ??
}