$sudoku = []
$color = []

$sectors = [[0,0], [1,0], [2,0], [0,1], [1,1], [2,1], [0,2], [1,2], [2,2]]
def secgroup(id)
  x = 3 * (id % 3)
  y = 3 * (id / 3)
  $sectors.map { |n| [n[0]+x, n[1]+y] }
end
def sec_id(x,y)
  $sectors.index([x / 3, y / 3])
end

def sdump(sid)
  9.times do |y|
    9.times { |x| print(sget(sid,x,y).is_a?(Numeric) ? sget(sid,x,y).to_s : " ") }
    print "\n"
  end
end

def sget(sid,x,y)
  $sudoku[sid][y][x]
end

def find_numbers(sid,positions,num)
  positions.map{ |p| sget(sid,p[0],p[1]) }.uniq
end

def recalculate(sid)
  9.times do |x| 9.times do |y|
    $sudoku[sid][y][x] = [1,2,3,4,5,6,7,8,9] if !$sudoku[sid][y][x].is_a? Numeric
  end end
  9.times do |y| 9.times do |x|
    if !$sudoku[sid][y][x].is_a? Numeric
      related = secgroup(sec_id(x,y)) +
          [[0,y],[1,y],[2,y],[3,y],[4,y],[5,y],[6,y],[7,y],[8,y],[9,y],
           [x,0],[x,1],[x,2],[x,3],[x,4],[x,5],[x,6],[x,7],[x,8],[x,9]]
      $sudoku[sid][y][x] = $sudoku[sid][y][x] - find_num(sid,related,num)
    end
  end end
end

def srestr(sid,x,y,num)
  # restricts: num can't be on this field
  return if sget(sid,x,y).is_a? Numeric
  sset_array(sid,x,y, sget(sid,x,y).reject{ |c| c == num } )
end
def sset_scalar(sid,x,y,num)
  if !$sudoku[sid][y][x].is_a? Numeric and !$sudoku[sid][y][x].include?(num)
    puts "WARNING: sset called with invalid num #{num}"
    return
  end
#  puts "LL #{x} #{y} #{num}"
  $sudoku[sid][y][x] = num
  secmem = secgroup(sec_id(x,y))
  9.times do |n|
    srestr(sid,n,y,num); srestr(sid,x,n,num)
    srestr(sid,secmem[n][0],secmem[n][1],num)
  end
  if $color[sid][y][x]
    $sudoku.length.times do |zsid| 9.times do |zx| 9.times do |zy|
      if $color[sid][y][x] == $color[zsid][zy][zx]
#        puts "LL #{x} #{y} #{num}"
        $sudoku[zsid][zy][zx] = num
      end
    end end end
  end
end
def sset_array(sid,x,y,num)
#  puts "LL #{x} #{y} #{num}"
  $sudoku[sid][y][x] = num
  if $color[sid][y][x]
    $sudoku.length.times do |zsid| 9.times do |zx| 9.times do |zy|
      if $color[sid][y][x] == $color[zsid][zy][zx]
#        puts "LL #{x} #{y} #{num & $sudoku[zsid][zy][zx]}"
        $sudoku[zsid][zy][zx] = num & $sudoku[zsid][zy][zx]
      end
    end end end
  end
end
def sset(sid,x,y,num)
  puts "#{x} #{y} #{num}" if num.is_a? Numeric or num.length < 9
  num = num[0] if !num.is_a? Numeric and num.length == 1 
  if num.is_a? Numeric
    sset_scalar(sid,x,y,num)
  else
    sset_array(sid,x,y,num)
  end
  $sudoku.length.times do |zsid| 9.times do |zx| 9.times do |zy|
    if $sudoku[zsid][zy][zx].is_a? Array and $sudoku[zsid][zy][zx].length == 1
      sset(zsid,zx,zy,sget(zsid,zx,zy))
    end
  end end end
end

$pass_count = 0

def pass(sid)
  $pass_count = $pass_count + 1
  puts "===== PASS #{$pass_count}, SUDOKU #{sid} ====="
  
  # check rows for unique numbers
  9.times do |num| 9.times do |y|
    found = nil
    9.times do |x|
      if !sget(sid,x,y).is_a? Numeric and sget(sid,x,y).include? num
        found = true if found
        found = x if !found
      end
    end
    sset(sid,found,y,num) if found.is_a? Numeric
  end end
  
  # check columns for unique numbers
  9.times do |num| 9.times do |x|
    found = nil
    9.times do |y|
      if !sget(sid,x,y).is_a? Numeric and sget(sid,x,y).include? num
        found = true if found
        found = y if !found
      end
    end
    sset(sid,x,found,num) if found.is_a? Numeric
  end end
  
  # check sectors for unique numbers
  9.times do |num| 9.times do |sector|
    secmem = secgroup(sector)
    found = nil
    9.times do |pos|
      x = secmem[pos][0]
      y = secmem[pos][1]
      if !sget(sid,x,y).is_a? Numeric and sget(sid,x,y).include? num
        found = true if found
        found = [x,y] if !found
      end
    end
    sset(sid,found[0],found[1],num) if found.is_a? Array
  end end
end

def pass_all
  $sudoku.length.times { |i| pass i }
end

def create_new
  Array.new(9).map{Array.new(9).map{[1,2,3,4,5,6,7,8,9]}}
end

def empty_color
  Array.new(9).map{Array.new(9)}
end

def load(file)
  sid = $sudoku.length
  puts "LOADING SUDOKU #{sid}"
  $sudoku << create_new
  $color << empty_color
  
  file.gets # separator
  9.times do |y|
    line = file.gets.chomp
    9.times do |x|
      policko = line[2*x,1]
      $color[sid][y][x] = policko if policko != " "
      policko = line[2*x+1,1]
      if policko != " " and policko.to_i == 0
        puts "ERROR: invalid input syntax at char #{2*x+2} line #{y+1} of sudoku #{sid+1}"
        exit
      end
      $sudoku[sid][y][x] = policko.to_i if policko != " "
    end
  end
  
  9.times do |y| 9.times do |x|
    sset(sid,x,y,sget(sid,x,y))
  end end
end

def loadf(filename = "sudoku1.txt")
  File.open(filename) do |f|
    f.gets.to_i.times { load f }
  end
end