數獨
python
def same_row(i, j): return (i//9 == j//9)
def same_col(i, j): return (i-j) % 9 == 0
def same_block(i, j): return (i//27 == j//27 and i % 9//3 == j % 9//3)
def solveSudoku(board):
ans = []
idx = board.index('.') if '.' in board else -1
if idx == -1: # 解完了
return [board]
exclude = {board[j] for j in range(81) if same_row(
idx, j) or same_col(idx, j) or same_block(idx, j)}
for m in set('123456789')-exclude:
ans += solveSudoku(board[:idx]+[m]+board[idx+1:])
return ans
sudoku = \
["5", "3", ".", ".", "7", ".", ".", ".", ".",
"6", ".", ".", "1", "9", "5", ".", ".", ".",
".", "9", "8", ".", ".", ".", ".", "6", ".",
"8", ".", ".", ".", "6", ".", ".", ".", "3",
"4", ".", ".", "8", ".", "3", ".", ".", "1",
"7", ".", ".", ".", "2", ".", ".", ".", "6",
".", "6", ".", ".", ".", ".", "2", "8", ".",
".", ".", ".", "4", "1", "9", ".", ".", "5",
".", ".", ".", ".", "8", ".", ".", "7", "9"]
ans = solveSudoku(sudoku)[0]
for i in range(9):
for j in range(9):
print(ans[i * 9 + j], end=' ')
print()Contributors
lucashsu95