#include <iostream>
#include <string>
#include <vector>
int main() {
	int n;
	std::cin >> n;
	const std::vector<int> flags{ 1,2,4,8,16,32,64,128,256,512 };
	int flag = ~0;
	for (; n > 0; --n) {
		int a, b, c, d;
		std::string res;
		std::cin >> a >> b >> c >> d >> res;
		int bit = 0;
		for (const auto &f : { a, b, c, d }) {
			bit |= flags.at(f);
		}
		if (res == "NO") {
			flag &= (~bit);
		}
		else {
			flag &= bit;
		}
	}
	for (auto i = 0; i < 10; ++i) {
		if ((flags.at(i) & flag) != 0) {
			std::cout << i << std::endl;
			break;
		}
	}
	return 0;
}