#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <queue>
#include <cmath>
#include <stack>

bool isKadomatsu(int kadomatsu[]) {
	if (   (kadomatsu[0] < kadomatsu[1] && kadomatsu[1] > kadomatsu[2])
		|| (kadomatsu[0] > kadomatsu[1] && kadomatsu[1] < kadomatsu[2])) {
		return true;
	}
	return false;
}

int main (void){
	int kadomatsu[3] = { 0 };
	int pos = 0;


	for (size_t i = 0; i < 3; i++)
	{
		char num;
		std::cin >> num;

		if (num == '?') {
			pos = i;
		}
		else {
			kadomatsu[i] = (int)(num - '0');
		}
	}

	kadomatsu[pos] = 1;
	if (isKadomatsu(kadomatsu)) {
		std::cout << 1;
	}

	kadomatsu[pos] = 4;
	if (isKadomatsu(kadomatsu)) {
		std::cout << 4;
	}

	return 0;
}