esm_doukaku #02 (素振り)

doukaku.rb

require 'bundler'
Bundler.require

MAP = {
  'A' => {
    'R' => 'H',
    'W' => 'I',
  },
  'I' => {
    'R' => 'F',
    'W' => 'G',
  },
  'G' => {
    'R' => 'D',
    'W' => 'E',
  },
  'E' => {
    'R' => 'B',
    'W' => 'C',
  },
  'C' => {
    'R' => 'J',
    'W' => 'A',
  },
  'H' => {
    'R' => 'J',
    'W' => 'C',
  },
  'J' => {
    'R' => 'B',
    'W' => 'E',
  },
  'B' => {
    'R' => 'D',
    'W' => 'G',
  },
  'D' => {
    'R' => 'F',
    'W' => 'I',
  },
  'F' => {
    'R' => 'H',
    'W' => 'A',
  }
}

def solve(input)
  start_point, *ops = input.chars

  current_point = start_point

  ([start_point] + ops.map {|op| current_point = MAP[current_point][op] }).join
end

def test(input, expected)
  actual = solve(input)
  raise "#{expected}, but got #{actual}" unless actual == expected
  puts "passed #{input}"
end

test("AW", "AI")
test("GR", "GD")
test("GW", "GE")
test("IR", "IF")
test("HR", "HJ")
test("BWW", "BGE")
test("ARW", "AHC")
test("GRR", "GDF")
test("BWR", "BGD")
test("JWWW", "JECA")
test("DRRR", "DFHJ")
test("CWWR", "CAIF")
test("HWWW", "HCAI")
test("GWRWR", "GEBGD")
test("FRRRW", "FHJBG")
test("JRRWW", "JBDIG")
test("JWWRRW", "JECJBG")
test("GRRRWW", "GDFHCA")
test("BRWRWR", "BDIFAH")
test("IRWRRWR", "IFAHJEB")
test("IWWWRRW", "IGECJBG")
test("GWWRWWR", "GECJECJ")
test("HRRWRWRW", "HJBGDIFA")
test("FRWWWRRW", "FHCAIFHC")
test("HRWWWRWRW", "HJECAHCJE")
test("CWWWRRWWW", "CAIGDFAIG")
test("BRRRWRRRRW", "BDFHCJBDFA")
test("FRWRRWRRWW", "FHCJBGDFAI")
test("GWRRRRWRWRW", "GEBDFHCJEBG")
test("DRWWWWWWRRW", "DFAIGECAHJE")
test("ARRRRWRRRRWW", "AHJBDIFHJBGE")
test("AWWWWWWRRWRR", "AIGECAIFHCJB")
test("JWWWRRWRWRWWR", "JECAHJEBGDIGD")
test("CRWRWRRWWWRWW", "CJEBGDFAIGDIG")
test("DWRWRWRWRWWRWW", "DIFAHCJEBGEBGE")
test("GRWWWRRRRWRWRR", "GDIGEBDFHCJEBD")
test("ARWWWRWWRWWWWWW", "AHCAIFAIFAIGECA")
test("DWRWRRWRWWRWWRW", "DIFAHJEBGEBGEBG")
test("JRWRRRRRWRRRRRWR", "JBGDFHJBGDFHJBGD")
test("IRWWRRWWWWWRRWWR", "IFAIFHCAIGEBDIGD")

Gemfile

source "https://rubygems.org"

gem 'pry'
gem 'activesupport', require: 'active_support/all'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    activesupport (4.2.5)
      i18n (~> 0.7)
      json (~> 1.7, >= 1.7.7)
      minitest (~> 5.1)
      thread_safe (~> 0.3, >= 0.3.4)
      tzinfo (~> 1.1)
    coderay (1.1.0)
    i18n (0.7.0)
    json (1.8.3)
    method_source (0.8.2)
    minitest (5.8.3)
    pry (0.10.3)
      coderay (~> 1.1.0)
      method_source (~> 0.8.1)
      slop (~> 3.4)
    slop (3.6.0)
    thread_safe (0.3.5)
    tzinfo (1.2.2)
      thread_safe (~> 0.1)

PLATFORMS
  ruby

DEPENDENCIES
  activesupport
  pry

BUNDLED WITH
   1.10.6