#include<bits/stdc++.h>
using namespace std;
const int N=2e5+10;
const int mod=998244353;
char s[N];
int main(){
	scanf("%s",s);
	int n=strlen(s);
	int s1=0,s2=0,ans=0,sum=1;
	for (int i=0;i<n;i++){
		if (s[i]=='0'){
			ans=(ans+s2)%mod;
			s1=(s1+sum)%mod;
		}else if (s[i]=='1'){
			s2=(s2+s1)%mod;
		}else{
			ans=(2ll*ans%mod+s2)%mod;
			s2=(2ll*s2%mod+s1)%mod;
			s1=(2ll*s1%mod+sum)%mod;
			sum=2ll*sum%mod;
		}
	}
	printf("%d\n",ans);
}