192 lines
3.8 KiB
Ruby
192 lines
3.8 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
require 'forwardable'
|
|
|
|
module Intcode
|
|
def self.read(filename)
|
|
parse File.read(filename)
|
|
end
|
|
|
|
def self.parse(input)
|
|
parsed = input
|
|
.gsub(/^#.*$/, '')
|
|
.gsub('\s', '')
|
|
.split(',')
|
|
.map(&:to_i)
|
|
Program.new parsed
|
|
end
|
|
|
|
class Program
|
|
def initialize(mem)
|
|
@input = nil
|
|
@initial_state = mem
|
|
end
|
|
|
|
def run(&user_input)
|
|
mem = Memory.new(@initial_state.clone)
|
|
Executor.new(mem).run(&user_input)
|
|
end
|
|
end
|
|
|
|
class Memory
|
|
extend Forwardable
|
|
|
|
def_delegator :@cells, :[]
|
|
def_delegator :@cells, :[]=
|
|
|
|
def initialize(cells)
|
|
@cells = cells
|
|
end
|
|
|
|
def to_s
|
|
batch_size = 10
|
|
output = String.new
|
|
@cells.each_slice(batch_size).each_with_index do |batch, idx|
|
|
prefix = idx * batch_size
|
|
output << "#{prefix}: #{batch.join(' ')}\n"
|
|
end
|
|
output
|
|
end
|
|
end
|
|
|
|
class DoneExecuting < StandardError; end
|
|
|
|
class Executor
|
|
def initialize(mem)
|
|
@mem = mem
|
|
@ip = 0
|
|
end
|
|
|
|
def run(&user_input)
|
|
loop do
|
|
tick(&user_input)
|
|
rescue DoneExecuting
|
|
# TODO: Stop using exceptions for control flow
|
|
return
|
|
end
|
|
end
|
|
|
|
def tick(&user_input)
|
|
opcode = operation(@mem[@ip])
|
|
mode = modes(@mem[@ip])
|
|
case opcode
|
|
when 1
|
|
r1, r2, r3 = @mem[@ip + 1, 3]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
raise StandardError, "unexpected mode: #{mode[2]}" if mode[2] != 0
|
|
|
|
@mem[r3] = a + b
|
|
@ip += 4
|
|
when 2
|
|
r1 = @mem[@ip + 1]
|
|
r2 = @mem[@ip + 2]
|
|
r3 = @mem[@ip + 3]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
raise StandardError, "unexpected mode: #{mode[2]}" if mode[2] != 0
|
|
|
|
@mem[r3] = a * b
|
|
@ip += 4
|
|
when 3
|
|
r1 = @mem[@ip + 1]
|
|
raise StandardError, "unexpected mode: #{mode[0]}" if mode[0] != 0
|
|
|
|
@mem[r1] = user_input.nil? ? input : user_input.call
|
|
@ip += 2
|
|
when 4
|
|
r1 = @mem[@ip + 1]
|
|
output = param(r1, mode[0])
|
|
puts "output: #{output}"
|
|
|
|
@ip += 2
|
|
when 5
|
|
r1 = @mem[@ip + 1]
|
|
r2 = @mem[@ip + 2]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
if !a.zero?
|
|
@ip = b
|
|
else
|
|
@ip += 3
|
|
end
|
|
when 6
|
|
r1 = @mem[@ip + 1]
|
|
r2 = @mem[@ip + 2]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
if a.zero?
|
|
@ip = b
|
|
else
|
|
@ip += 3
|
|
end
|
|
when 7
|
|
r1 = @mem[@ip + 1]
|
|
r2 = @mem[@ip + 2]
|
|
r3 = @mem[@ip + 3]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
raise StandardError, "unexpected mode: #{mode[2]}" if mode[2] != 0
|
|
|
|
@mem[r3] = a < b ? 1 : 0
|
|
@ip += 4
|
|
when 8
|
|
r1 = @mem[@ip + 1]
|
|
r2 = @mem[@ip + 2]
|
|
r3 = @mem[@ip + 3]
|
|
a = param(r1, mode[0])
|
|
b = param(r2, mode[1])
|
|
raise StandardError, "unexpected mode: #{mode[2]}" if mode[2] != 0
|
|
|
|
@mem[r3] = a == b ? 1 : 0
|
|
@ip += 4
|
|
when 99
|
|
raise DoneExecuting
|
|
else
|
|
raise StandardError, "unexpected opcode: #{opcode}"
|
|
end
|
|
end
|
|
|
|
private
|
|
|
|
def input
|
|
print 'input> '
|
|
return default_input if @input.nil?
|
|
|
|
inp = @input.call
|
|
puts inp
|
|
inp
|
|
end
|
|
|
|
def default_input
|
|
gets.to_i
|
|
end
|
|
|
|
def operation(cell)
|
|
(cell % 100)
|
|
end
|
|
|
|
def modes(cell)
|
|
m = Hash.new(0)
|
|
(cell / 100).truncate.digits.each_with_index do |d, i|
|
|
m[i] = d
|
|
end
|
|
m
|
|
end
|
|
|
|
def param(val, mode)
|
|
case mode
|
|
when 0
|
|
@mem[val]
|
|
when 1
|
|
val
|
|
else
|
|
raise StandardError, "unexpected mode: #{mode}"
|
|
end
|
|
end
|
|
|
|
# Operators
|
|
|
|
def add; end
|
|
end
|
|
end
|