#include <bits/stdc++.h>
using namespace std;

int main() {
  char x[3];
  int n;
  for (int i = 0; i < 3; i++) {
    cin >> x[i];
    if (x[i] == '?') n = i;
  }

  string ans = "";

  for (int i = 0; i < 2; i++) {
    char t = i == 0 ? '1' : '4';
    x[n] = t;
    if ((x[1] < x[0] && x[1] < x[2]) || (x[1] > x[0] && x[1] > x[2])) ans += t;
  }

  cout << ans << endl;
  return 0;
}