#include <bits/stdc++.h>
using namespace std;

long long mod = 998244353;
long long Fact[1 << 19];
long long Inv[1 << 19];

long long modpow(long long a, long long b, long long m) {
	long long p = 1, q = a;
	for (int i = 0; i < 30; i++) {
		if ((b >> i) & 1) { p *= q; p %= m; }
		q *= q; q %= m;
	}
	return p;
}

long long Division(long long a, long long b, long long m) {
	return (a * modpow(b, m - 2, m)) % m;
}

void Initialize() {
	Fact[0] = 1;
	for (int i = 1; i <= 300000; i++) Fact[i] = (1LL * i * Fact[i - 1]) % mod;
	for (int i = 0; i <= 300000; i++) Inv[i] = Division(1, Fact[i], mod);
}

long long ncr(int n, int r) {
	if (n < r || r < 0) return 0;
	return (Fact[n] * Inv[r] % mod) * Inv[n - r] % mod;
}

int main() {
	string S; cin >> S;
	Initialize();
	if (S.size() % 2 == 1) {
		cout << "0" << endl;
		return 0;
	}
	int rem1 = S.size() / 2;
	int rem2 = S.size() / 2;
	for (int i = 0; i < S.size(); i++) {
		int c = (S[i] - '0'); c ^= (i % 2);
		if (S[i] == '?') continue;
		if (c == 0) rem1--;
		if (c == 1) rem2--;
	}
	cout << ncr(rem1 + rem2, rem1) << endl;
	return 0;
}