#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    char c[3];
    rep(i,3) cin >> c[i];

    string ans = "";
    for(char x : {'1', '4'}) {
        rep(i,3) if(c[i] == '?') c[i] = x;

        auto [mi, ma] = minmax({c[0], c[1], c[2]});
        if(c[1] == mi || c[1] == ma) ans += x;

        rep(i,3) if(c[i] == x) c[i] = '?';
    }
    cout << ans << endl;
}