javaamb.txt

java解决数独问题

class Sudoku   
  def initialize   
    @square = Array.new(9) { Array.new(9) {0} }   
    @amb = Amb.new  
  end   
  
  def find_sudoku   
    9.times do |row|   
       9.times do |col|   
          candidate = @amb.choose(*range)   
          @square[row][col] = 0  
          @amb.assert(count_in_row(row, candidate) == 0)   
          @amb.assert(count_in_col(col, candidate) == 0)   
          @amb.assert(count_in_sub_square(row, col, candidate) == 0)   
          @square[row][col] = candidate   
       end   
    end   
  end   
  
  def range   
    result,range = [], [1,2,3,4,5,6,7,8,9]   
    9.times do  
       result << range[index = rand(range.size)]   
       range.delete_at index   
    end   
    result   
  end   
    
  def count_in_row row, candidate   
    @square[row].inject(0) {|count, num| (num == candidate) ? count + 1 : count}   
  end   
  
  def count_in_col col, candidate   
    @square.inject(0) {|count, row| (row[col] == candidate) ? count + 1 : count}   
  end   
  
  def count_in_sub_square row, col, candidate   
    start_row, start_col = row / 3, col / 3  
    count = 0  
    3.times {|i| 3.times {|j| count += 1 if @square[start_row * 3 + i][start_col * 3 + j] == candidate}}   
    count   
  end   
    
  def create_sudoku number   
    find_sudoku       
    number.times { @square[rand(9)][rand(9)] = 0}   
  end   
  
  def next   
    begin   
      @amb.failure   
      create_sudoku   
    rescue Amb::ExhaustedError   
      raise 'no more Sudoku'  
    end   
  end   
  
  def inspect   
    result = ""  
    9.times do |row|   
       9.times {|col| result << (@square[row][col] == 0 ? '?' : @square[row][col].to_s) << ' '}   
       result << "\n"  
    end   
    result   
  end   
end   
  
sudoku = Sudoku.new  
sudoku.create_sudoku 30  
p sudoku