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#!/usr/bin/env ruby

class Machine
  def initialize(starting_memory = [])
    @mem = starting_memory
    @pc = 0
    @halt = false
    @wait = false
    @buffered_input = []
    @buffered_output = []
    @relative_base = 0
  end

  def mem(start = 0, len = @mem.length)
    @mem[start...(start + len)]
  end

  def halt!
    @halt = true
  end

  def halt?
    @halt
  end

  def wait!
    @wait = true
  end

  def wait?
    t = @wait
    @wait = false
    t
  end

  def buffer_input(x)
    if x.is_a?(Array) then
      @buffered_input += x
    else
      @buffered_input.push(x)
    end
  end

  def buffered_output
    t = @buffered_output
    @buffered_output = []
    t
  end

  def step
    return if halt?

    opcode = @mem[@pc] % 100

    if opcode == 99 then
      halt!
      @pc += 1
      return
    end

    p3, p2, p1 = ("%03d" % (@mem[@pc] / 100)).chars

    l1w, l1r = get(p1, 1)
    l2w, l2r = get(p2, 2) if [1,2,5,6,7,8].include?(opcode)
    l3w, l3r = get(p3, 3) if [1,2,7,8].include?(opcode)

    case opcode
    when 1
      @mem[l3w] = l1r + l2r
      @pc += 4
    when 2
      @mem[l3w] = l1r * l2r
      @pc += 4
    when 3
      if @buffered_input.empty? then
        wait!
        return
      end
      @mem[l1w] = @buffered_input.shift
      @pc += 2
    when 4
      @buffered_output.push(l1r)
      @pc += 2
    when 5
      @pc = (l1r != 0 ? l2r : @pc + 3)
    when 6
      @pc = (l1r == 0 ? l2r : @pc + 3)
    when 7
      @mem[l3w] = (l1r < l2r ? 1 : 0)
      @pc += 4
    when 8
      @mem[l3w] = (l1r == l2r ? 1 : 0)
      @pc += 4
    when 9
      @relative_base += l1r
      @pc += 2
    end
  end

  def run
    until halt? || wait? do
      step
    end
  end

  private

  def get(p, a)
    w = case p
        when "0"
          @mem[@pc + a]
        when "2"
          @relative_base + @mem[@pc + a]
        end
    r = case p
        when "0"
          @mem[@mem[@pc + a]]
        when "1"
          @mem[@pc + a]
        when "2"
          @mem[@relative_base + @mem[@pc + a]]
        end
    [w, r || 0]
  end
end

input = $stdin.readlines[0].strip.split(",").map(&:to_i)

m = Machine.new(input)
m.buffer_input(2)

m.run
puts m.buffered_output