count = gets.chomp.to_i
list = Array.new
count.times do
	array = gets.split.map(&:to_s)
	if array[-1] == "YES"
		array.each{|arg| list << arg.to_i if arg =~ /^[0-9]+$/} 
	else
		array.each{|arg| list.delete(arg.to_i) if arg =~ /^[0-9]+$/}
	end
end
puts list.uniq.sort{|x,y| list.count(y) <=> list.count(x) }[0]