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#!/usr/bin/env ruby

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

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

  def halt!
    @halt = true
  end

  def halt?
    @halt
  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.map{|c|c == "1"}

    l1w = @mem[@pc + 1]
    l1r = p1 ? l1w : @mem[l1w]
    l2w = @mem[@pc + 2]
    l2r = p2 ? l2w : @mem[l2w]
    l3w = @mem[@pc + 3]
    l3r = p3 ? l3w : @mem[l3w]

    case opcode
    when 1
      @mem[l3w] = l1r + l2r
      @pc += 4
    when 2
      @mem[l3w] = l1r * l2r
      @pc += 4
    when 3
      @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
    end
  end

  def run
    until halt? do
      step
    end
  end
end

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

max = 0
(0..4).to_a.permutation.each do |p|
  a = Machine.new(input.dup)
  b = Machine.new(input.dup)
  c = Machine.new(input.dup)
  d = Machine.new(input.dup)
  e = Machine.new(input.dup)

  a.buffer_input(p[0])
  b.buffer_input(p[1])
  c.buffer_input(p[2])
  d.buffer_input(p[3])
  e.buffer_input(p[4])

  a.buffer_input([0] * input.count(3))
  a.run
  b.buffer_input(a.buffered_output)
  b.run
  c.buffer_input(b.buffered_output)
  c.run
  d.buffer_input(c.buffered_output)
  d.run
  e.buffer_input(d.buffered_output)
  e.run

  s = e.buffered_output.last
  max = s if s > max
end

puts max