sample.unsolved.txt

096040001100060004504810390007950043030080000405023018010630059059070830003590007
302609005500730000000000900000940000000000109000057060008500006000000003019082040
000075400000000008080190000300001060000000034000068170204000603900000020530200000
300000000050703008000028070700000043000000000003904105400300800100040000968000200
290500007700000400004738012902003064800050070500067200309004005000080700087005109
080020000040500320020309046600090004000640501134050700360004002407230600000700450
608730000200000460000064820080005701900618004031000080860200039050000100100456200
370000001000700005408061090000010000050090460086002030000000000694005203800149500
030500804504200010008009000790806103000005400050000007800000702000704600610300500
000689100800000029150000008403000050200005000090240801084700910500000060060410000

sudoku.rb

class Sudoku
  def initialize(board_string)
  end
 
  def solve!
  end
 
  # Returns a string representing the current state of the board
  # Don't spend too much time on this method; flag someone from staff
  # if you are.
  def board
 
  end
end
 
# The file has newlines at the end of each line, so we call
# String#chomp to remove them.
board_string = File.readlines('sample.unsolved.txt').first.chomp
 
game = Sudoku.new(board_string)
 
# Remember: this will just fill out what it can and not "guess"
game.solve!
 
puts game.board