N = gets.to_i
x = [0,1,2,3,4,5,6,7,8,9]

N.times do |i|
  a = gets.split
  b = a[0..3].map(&:to_i)
  if a[4] == "NO"
    x -= b
  else
    x = x & b
  end

  if x.size == 1
    puts x
    exit
  end
end