#include <iostream>
#include <string>

int main(void){
	int a[3];
	std::string s;
	for (int i = 0; i < 3; i++){
		std::cin >> s;
		if (s[0] == '?')a[i] = -1;
		else a[i] = std::stoi(s);
	}
	if (a[1] == -1)std::cout << "1";
	std::cout << "4" << std::endl;
	return 0;
}