LeetCode 题解(231) : Valid Sudoku

题目：

Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules.

The Sudoku board could be partially filled, where empty cells are filled with the character'.'.

A partially filled sudoku which is valid.

Note:
A valid Sudoku board (partially filled) is not necessarily solvable. Only the filled cells need to be validated.

题解：

C++和Java版略显笨重，这里就不给出了。Python版如下

class Solution(object):
    def isValidSudoku(self, board):
        """
        :type board: List[List[str]]
        :rtype: bool
        """
        rows, cols, cells = [[] for i in range(9)], [[]for i in range(9)], [[] for i in range(9)]
        for i in range(len(board)):
            for j in range(len(board[0])):
                e = board[i][j]
                if e != '.':
                    if e in rows[i] or e in cols[j] or e in cells[(i / 3) * 3 + j / 3]:
                        return False
                    else:
                        rows[i].append(e)
                        cols[j].append(e)
                        cells[(i / 3 * 3 + j / 3)].append(e)
        return True