#include <iostream>

int candidate[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};

int main(void)
{
	int N;
	
	std::cin >> N;
	
	int num[4][N]; //num[number][turn]
	int yn[N];
	
	for(int i = 0; i < N; i ++)
	{
		std::string YN;
	
		std::cin >> num[0][i] >> num[1][i] >> num[2][i] >> num[3][i] >> YN;
		
		if(YN == "YES")
		{
			yn[i] = 1;
		}
		else
		{
			yn[i] = 0;
		}
	}
	
	for(int i = 0; i < N; i ++)
	{
		if(yn[i] == 1)
		{
			for(int j = 0; j < 10; j ++)
			{
				if(j != num[0][i] && j != num[1][i] && j != num[2][i] && j != num[3][i])
				{
					candidate[j] = -1;
				}
			}
		}
		else
		{
			for(int j = 0; j < 10; j ++)
			{
				if(j == num[0][i] || j == num[1][i] || j == num[2][i] || j == num[3][i])
				{
					candidate[j] = -1;
				}
			}
		}
	}
	
	int ans;
	
	for(int i = 0; i < 10; i ++)
	{
		if(candidate[i] != -1)
		{
			ans = candidate[i];
		}
	}
	
	std::cout << ans << std::endl;

	return 0;
}