#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <string>

using namespace std;
bool is_kado(int a, int b, int c) {
	if (a == b || b == c || c == a) {
		return false;
	}

	if (a < b && b > c) {
		return true;
	}
	if (a > b && b < c) {
		return true;
	}
	return false;
}

bool check(string a, string b, string c, int n) {
	int x, y, z;
	x = a == "?" ? n : stoi(a);
	y = b == "?" ? n : stoi(b);
	z = c == "?" ? n : stoi(c);

	return is_kado(x, y, z);
}

int main() {
	string a, b, c;
	cin >> a >> b >> c;

	bool is1 = check(a, b, c, 1);
	bool is4 = check(a, b, c, 4);

	string ans;
	if (is1) { ans += "1"; }
	if (is4) { ans += "4"; }
	cout << ans << endl;

	return 0;
}