#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

int main()
{
    vector<int> a(3, -1);
    for(int i=0; i<3; ++i){
        char c;
        cin >> c;
        if(isdigit(c))
            a[i] = c - '0';
    }

    for(int x : {1, 4}){
        vector<int> b = a;
        replace(b.begin(), b.end(), -1, x);
        if((b[0] < b[1]) ^ (b[1] < b[2]))
            cout << x;
    }
    cout << endl;

    return 0;
}