#include <string>
#include <iostream>
using namespace std;
using ll = long long;

#define rep(i, n) for(int i=0; i<n; ++i)

const ll mod = 998244353;

ll powm(ll x, ll n) {
    ll res = 1;
    while(n) {
        if(n & 1) {
            res *= x;
            res %= mod;
        }
        n >>= 1;
        x *= x;
        x %= mod;
    }
    return res;
}

int main() {
    ll n;
    string a;
    cin >> n >> a;
    ll w = 0, b = 0;
    ll res = 1;
    ll i = 0;
    while(i < n) {
        while(i < n && a[i] == '0') {
            w++;
            i++;
        }
        while(i < n && a[i] == '1') {
            b++;
            i++;
        }
        if(w > 0 && b > 0) {
            res *= (w + b + 1);
            res %= mod;
        }
        cerr << w << " " << b << endl;
        w = b = 0;
    }
    cout << res << endl;
    // ll m = 0;
    // rep(i, n-1) {
    //     if(a[i] == '0' && a[i+1] == '1') m++;
    // }
    // // n+m C m

    // vector<ll> power(1'000'000, 1);
    // for(int i=1; i<1'000'000; i++) {
    //     power[i] = power[i-1] * i;
    //     power[i] %= mod;
    // }

    // cout << power[n+m] * powm(power[m] * power[n] % mod, mod-2) % mod << endl;
    
}