#include <bits/stdc++.h>
#include <atcoder/all>

using namespace std;
using ll = long long;
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define all(x) begin(x), end(x)
template <class T> bool chmin(T& x, T y) {
	return x > y ? (x = y, true) : false;
}
template <class T> bool chmax(T& x, T y) {
	return x < y ? (x = y, true) : false;
}

using mint = atcoder::modint998244353;

void solve() {
	int n;
	cin >> n;
	string s;
	cin >> s;
	s.insert(s.begin(), '1');
	s.push_back('0');
	vector<pair<int, int>> vp = {{s[0], 0}};
	for (char c : s) {
		if (vp.back().first == c) vp.back().second++;
		else vp.push_back({c, 1});
	}
	int m = vp.size();
	mint ans = 1;
	for (int i = 1; i < m - 1; i += 2) {
		ans *= vp[i].second + vp[i + 1].second + 1;
	}
	cout << ans.val() << '\n';
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(15);
	int t = 1;
	// cin >> t;
	while (t--) solve();
}