class Row
  attr_reader :values

  def initialize(values)
    @values = values.sort.reverse
  end 

  def self.for(string)
    new string.split("\t").map(&:to_i) 
  end

  def to_s
    values.to_s
  end

  def difference
    values.first - values.last
  end

  def quotient
    x, y = values.combination(2).find { |a, b| a % b == 0 }
    x / y
  end
end

class Spreadsheet
  attr_reader :rows
  def initialize(rows)
    @rows = rows
  end

  def self.for(string)
    new string.split("\n").map{ |row| Row.for row }
  end

  def to_s
    rows.map(&:to_s).join("\n")
  end

  def checksum
    rows.map(&:difference).sum
  end

  def evenly_divisible_values
    rows.map(&:quotient).sum
  end
end

sheet = Spreadsheet.for STDIN.read.chomp

part_1 = sheet.checksum
puts "Part 1: #{part_1}"

part_2 = sheet.evenly_divisible_values
puts "Part 2: #{part_2}"