#include<iostream>
#include<stdio.h>
#include<algorithm>
#include<vector>
#include<string.h>
#include<math.h>
#include<map>
#include<iomanip>
#include<queue>

const long long INF = 1e6+7;
const long long MOD = 1e9+7;
const double PI=acos(-1);

using namespace std;

int main(){
	vector<int> cA,cB;
	for(int i=0;i<3;i++){
		char temp;
		cin >> temp;
		if(temp=='?'){
			temp='1';
			cA.push_back((int)(temp-'0'));
			temp='4';
			cB.push_back((int)(temp-'0'));
		}else{
			cA.push_back((int)(temp-'0'));
			cB.push_back((int)(temp-'0'));
		}
	}
	string ans="";
	int temp=cA[1];
	sort(cA.begin(),cA.end());
	if(temp==cA[0] || temp==cA[2]){
		ans+="1";
	}
	temp=cB[1];	
	sort(cB.begin(),cB.end());
	if(temp==cB[0] || temp==cB[2]){
		ans+="4";
	}
	sort(ans.begin(),ans.end());
	cout << ans << endl;
	return 0;
}