class CPU
  def initialize
    @x = 1
    @cycle = 1
    @iq = []
  end

  attr_reader :x, :cycle

  def enq(op, arg = 0)
    @iq << [
      arg,
      case op
      when 'noop'; 1
      when 'addx'; 2
      end
    ]
  end

  def done?
    @iq.empty?
  end

  def clock
    istr = @iq[0]
    istr[1] -= 1
    if istr[1] == 0
      @x += istr[0]
      @iq.shift
    end
    @cycle += 1
  end
end

cpu = CPU.new

istrs = $stdin.readlines.map(&:strip).map(&:split)
istrs.each do |istr|
  cpu.enq(istr[0], istr[1]&.to_i || 0)
end

strsum = 0
until cpu.done?
  c = cpu.cycle
  x = cpu.x

  strsum += (c * x) if (c - 20) % 40 == 0
  cpu.clock
end

puts strsum