count = gets.chomp.to_i
list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
yes_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
count.times do
	array = gets.split.map(&:to_s)
	result_array = Array.new
	if array[4] == "YES"
		for val in array do
			val = 10 if val.to_i == 0
			yes_list.delete(val.to_i)
		end 
		for val in yes_list do
			list.delete(val.to_i)
		end 
		yes_list = [10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
	elsif array[4] == "NO"
		for val in array do
			val = 10 if val.to_i == 0
			list.delete(val.to_i)
		end 
	end
end
result = list[0] == 10 ? 0 : list[0]
puts result