#include <bits/stdc++.h>
#define SORT(x) sort((x).begin(), (x).end())
#define ALL(x) (x).begin(), (x).end()
#define rep(i, n) for (ll i = 0; i < n; i++)
#define reps(i, m, n) for (ll i = m; i < n; i++)
#define repr(i, m, n) for (ll i = m; i >= n; i--)
#define de(x) cout << #x << "=" << x << endl;
template <class T> bool maxi(T &a, const T &b) {
    if (a < b) { a = b; return 1;} return 0;}
template <class T> bool mini(T &a, const T &b) {
    if (b < a) { a = b; return 1;} return 0;}
#define dame {cout<< "-1" <<"\n"; return;}
#define INF2 1000000000000000037
#define INF  1000000007
#define MOD  998244353
using namespace std;
using ll = long long;
using ld = long double;
using P  = pair<ll,ll>;
//--GLOBAL---------------------------------
template< int mod >
struct ModInt {
    int x;

    ModInt() : x(0) {}
    ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}

    ModInt &operator+=(const ModInt &p) {
        if((x += p.x) >= mod) x -= mod;
        return *this;
    }
    ModInt &operator-=(const ModInt &p) {
        if((x += mod - p.x) >= mod) x -= mod;
        return *this;
    }
    ModInt &operator*=(const ModInt &p) {
        x = (int) (1LL * x * p.x % mod);
        return *this;
    }
    ModInt &operator/=(const ModInt &p) {
        *this *= p.inverse();
        return *this;
    }

    ModInt operator-() const { return ModInt(-x); }

    ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }
    ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }
    ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }
    ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }
    bool operator==(const ModInt &p) const { return x == p.x; }
    bool operator!=(const ModInt &p) const { return x != p.x; }

    ModInt inverse() const {
        int a = x, b = mod, u = 1, v = 0, t;
        while(b > 0) {
            t = a / b;
            swap(a -= t * b, b);
            swap(u -= t * v, v);
        }
        return ModInt(u);
    }

    ModInt pow(int64_t n) const {
        ModInt ret(1), mul(x);
        while(n > 0) {
        if(n & 1) ret *= mul;
            mul *= mul;
            n >>= 1;
        }
        return ret;
    }

    friend ostream &operator<<(ostream &os, const ModInt &p) {
        return os << p.x;
    }
    friend istream &operator>>(istream &is, ModInt &a) {
        int64_t t;
        is >> t;
        a = ModInt< mod >(t);
        return (is);
    }
    static int get_mod() { return mod; }
};
using mint = ModInt< MOD >;
const ll MAX = 202020;
ll fac[MAX], finv[MAX], inv[MAX];
void cinit() { // O(nlogn)
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    reps(i, 2, MAX){
        fac[i] = fac[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }
}
ll c(int n, int k){ // 二項係数計算
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
mint dp[4020][2020];
//--MAIN-----------------------------------
void Main() {
    string S; cin>>S;
    ll N=S.size();
    dp[0][0]=1;
    rep(i,N){
        ll x='2'-S[i];
        rep(j,2010){
            ll jj=j+x;
            if(jj<=i+1) dp[i+1][jj]+=dp[i][j];
            jj-=1;
            if(jj>=0) dp[i+1][jj]+=dp[i][j];   
        }
    }
    reps(i,N,N*2){
        rep(j,2010){
            ll jj=j;
            dp[i+1][jj]+=dp[i][j];
            jj-=1;
            if(jj>=0) dp[i+1][jj]+=dp[i][j];   
        }
    }
    mint ans=dp[N*2][0];
    cout<< ans <<"\n";
}

//--START----------------------------------
int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(15);
    Main();
}
//-----------------------------------------


Measured memory_bytes: 33024