Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
- Each row must contain the digits 1-9 without repetition.
- Each column must contain the digits 1-9 without repetition.
- Each of the 9 3x3 sub-boxes of the grid must contain the digits 1-9 without repetition.
A partially filled sudoku which is valid.
The Sudoku board could be partially filled, where empty cells are filled with the character '.'.
Example 1:
Input:
[
["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"]
]
Output: true
Example 2:
Input:
[
["8","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"]
]
Output: false
Explanation: Same as Example 1, except with the 5 in the top left corner being
modified to 8. Since there are two 8's in the top left 3x3 sub-box, it is invalid.
Note:
- A Sudoku board (partially filled) could be valid but is not necessarily solvable.
- Only the filled cells need to be validated according to the mentioned rules.
- The given board contain only digits 1-9 and the character '.'.
- The given board size is always 9x9.
class Solution:
def isValidSudoku(self, board):
"""
:type board: List[List[str]]
:rtype: bool
"""
def line():
for i in range(9):
ans = [0 for _ in range(10)]
for j in range(9):
if board[i][j]=='.':
continue
ans[int(board[i][j])] += 1
for t in ans:
if t>1:
return False
return True
def coloum():
for j in range(9):
ans = [0 for _ in range(10)]
for i in range(9):
if board[i][j]=='.':
continue
ans[int(board[i][j])] += 1
# print(j,'
',ans)
for t in ans:
if t>1:
return False
return True
def boxes(a,b,c,d):
ans = [0 for _ in range(10)]
for i in range(a,b):
for j in range(c,d):
if board[i][j]=='.':
continue
ans[int(board[i][j])] += 1
for t in ans:
if t>1:
return False
return True
if line() and coloum() and boxes(0,3,0,3) and boxes(3,6,0,3) and boxes(6,9,0,3) and boxes(0,3,3,6) and boxes(3,6,3,6) and boxes(6,9,3,6) and boxes(0,3,6,9) and boxes(3,6,6,9) and boxes(6,9,6,9):
return True
return False