数独算法代码python

数独游戏可以通过编写算法来自动解决。Python是一种流行的编程语言，常用于编写算法。下面是一个简单的数独算法代码示例，用Python编写：

def solve_sudoku(board):
  find = find_empty(board)
  if not find:
    return True
  else:
    row, col = find

  for i in range(1,10):
    if valid(board, i, (row, col)):
      board[row][col] = i

      if solve_sudoku(board):
        return True

      board[row][col] = 0

  return False


def valid(board, num, pos):
  # Check row
  for i in range(len(board[0])):
    if board[pos[0]][i] == num and pos[1] != i:
      return False

  # Check column
  for i in range(len(board)):
    if board[i][pos[1]] == num and pos[0] != i:
      return False

  # Check 3x3 box
  box_x = pos[1] // 3
  box_y = pos[0] // 3

  for i in range(box_y*3, box_y*3 + 3):
    for j in range(box_x * 3, box_x*3 + 3):
      if board[i][j] == num and (i,j) != pos:
        return False

  return True


def print_board(board):
  for i in range(len(board)):
    if i % 3 == 0 and i != 0:
      print("- - - - - - - - - - - - -")

    for j in range(len(board[0])):
      if j % 3 == 0 and j != 0:
        print(" | ", end="")

      if j == 8:
        print(board[i][j])
      else:
        print(str(board[i][j]) + " ", end="")


def find_empty(board):
  for i in range(len(board)):
    for j in range(len(board[0])):
      if board[i][j] == 0:
        return (i, j)

  return None


board = [
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0]
]

# Update the board with valid numbers
board = [
  [0,2,3,0,0,0,0,8,0],
  [0,0,0,7,0,0,0,0,1],
  [6,0,0,0,0,2,0,0,0],
  [0,3,0,0,0,0,5,0,7],
  [0,0,9,0,2,0,6,3,0],
  [0,7,0,0,0,0,9,4,2],
  [7,0,0,0,0,9,0,0,0],
  [0,0,0,0,0,3,0,0,0],
  [2,0,1,0,0,0,0,6,0]
]

print_board(board)
solve_sudoku(board)
print("\nSolved Board:")
print_board(board)

这个算法的实现递归调用`find_empty`函数来查找空的格子，然后使用`valid`函数判断这个格子是否可以填写数字，如果可以则填写数字并通过递归调用进行下一步验证，如果无法填写，则返回上一个步骤继续寻找其他可行解。这个算法非常直接简单，适合初学者练习编写算法。

需要注意的是，这个算法并不一定可以解决所有的数独问题，有一些特定类型的问题可能无法解决。因此，如果您需要解决复杂的数独问题，请参考更复杂、更完整的算法实现。