#include #pragma GCC optimize("Ofast") using namespace std; using std::cout; using std::cin; using std::endl; using ll=long long; using ld=long double; ll ILL=2167167167167167167; const int INF=2100000000; const int mod=998244353; #define rep(i,a,b) for (ll i=a;i using _pq = priority_queue, greater>; template ll LB(vector &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();} template ll UB(vector &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();} template bool chmin(T &a,const T &b){if(a>b){a=b;return 1;}else return 0;} template bool chmax(T &a,const T &b){if(a void So(vector &v) {sort(v.begin(),v.end());} template void Sore(vector &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});} void yneos(bool a){if(a) cout<<"Yes\n"; else cout<<"No\n";} template void vec_out(vector &p){for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout< T min(vector &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;} template T max(vector &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;} template T sum(vector &a){assert(!a.empty());T ans=a[0]-a[0];for(auto &x:a) ans+=x;return ans;} void solve(); // oddloop int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int t=1; //cin>>t; rep(i,0,t) solve(); } void solve(){ string S; cin>>S; int N=S.size(); ll rev=(mod+1)/2; vector> p(N+1,vector(3)); auto f=[&](char c)->int{ if(c=='?') return 2; return c-'0'; }; rep(i,0,N) p[i+1]=p[i],p[i+1][f(S[i])]++; ll ans=0; rep(i,0,N){ if(S[i]=='0') continue; ll A=(p[i][0]+rev*p[i][2])%mod; ll B=(p[N][0]-p[i+1][0]+rev*(p[N][2]-p[i+1][2]))%mod; A=(A*B)%mod; if(S[i]=='?') ans=(ans+A*rev)%mod; else ans=(ans+A)%mod; } rep(i,0,p[N][2]) ans=(ans*2ll)%mod; cout<