require 'json'
require 'pry'

TZ = %w(
  America/New_York
  America/Chicago
  America/Denver
  America/Los_Angeles
  America/Kentucky/Louisville
  America/Indiana/Indianapolis
  America/Detroit
  America/Boise
  America/Phoenix
  America/Anchorage
  Pacific/Honolulu
  America/Indiana/Knox
  America/Indiana/Winamac
  America/Indiana/Vevay
  America/Indiana/Marengo
  America/Indiana/Vincennes
  America/Indiana/Tell_City
  America/Indiana/Petersburg
  America/Menominee
  America/Shiprock
  America/Nome
  America/Juneau
  America/Kentucky/Monticello
  America/North_Dakota/Center
  America/Yakutat
)

TZS = Array.new(10) do
  Array.new(10) do
    Array.new(10) do
      Array.new(10) do
        Array.new(10) do
          nil
        end
      end
    end
  end
end

zips = JSON.parse(DATA.read)
zips.each do |zip, tz|
  z = zip.chars.map(&:to_i)
  TZS[z[0]][z[1]][z[2]][z[3]][z[4]] = tz
end

def reductor(ary)
  if ary.all? { |e| e.is_a?(Array) }
    ary.map!(&method(:reductor))
  end
  uniqs = ary.compact.uniq
  case uniqs.length
  when 0
    nil
  when 1
    uniqs.first
  else
    ary
  end
end

TZS = reductor(TZS)

def fetch(ary, *idxn)
  return ary unless ary.is_a?(Array)
  i = idxn.shift
  fetch(ary[i], *idxn)
end

def zip2tz(zip)
  fetch(TZS, *zip.chars.map(&:to_i))
end

zips.each do |zip, tz|
  next if tz == zip2tz(zip)
  p zip => tz
  exit
end

print TZS.to_json