#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vmi = vector<mint>;
using vvmi = vector<vmi>;
using vvvmi = vector<vvmi>;
#define all(a) (a).begin(), (a).end()
#define rep2(i, m, n) for (int i = (m); i < (n); ++i)
#define rep(i, n) rep2(i, 0, n)
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)

void solve(){
    
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n; cin >> n;
    string s; cin >> s;
    int j = 0, len = s.length();
    while(j < len && s[j] == '1')j++;
    if(j == len){
        cout << 1 << endl;
        return 0;
    }
    vi v;
    int c = 0;
    int b = 0;
    rep2(i, j, len){
        if(s[i] == '0'){
            if(b == 0){
                c++;
            }else{
                v.push_back(c);
                b = 0;
                c = 1;
            }
        }else{
            c++;
            if(b == 0)b = 1;
        }
    }
    if(b == 1)v.push_back(c);
    mint ans = 1;
    for(auto i : v){
        ans *= mint(i+1);
    }cout << ans.val() << endl;

    return 0;
}