string = readlines

string.each_with_index do |line, index|
  if index + 1 == string.length
    print "NO"
    return
  end
  length = line.length
  length.times do |i|
    index = i
    current_char = line[index]
    if current_char == "L"
      index = index + 1
      next_char = line[index]
      if next_char == "O"
        index = index + 1
        next_char = line[index]
        if next_char == "V"
          index = index + 1
          next_char = line[index]
          if next_char == "E"
            print "YES"
            return
          end
        end
      end
    end
  end

end