36. Valid Sudoku

problem

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.

判断一个数独是不是符合形式规则，加数正确与否不管

那么题目转换成每行每列井字的九个方块是不是0-9不重复

solution

• 大致思路

行直接判断内层list

列zip后判断内层tuple

井字截取三行，每行截取三个元素 3*3的循环，

class Solution(object):
    def isValidSudoku(self, board):
        """
        :type board: List[List[str]]
        :rtype: bool
        """
        for elem in board:
            if not self.verfiy(elem):
                return False
        row = zip(*board)
        for elem in row:
            if not self.verfiy(elem):
                return False
        for i in range(3):
            for j in range(3):
                elem = []
                elem.extend(board[i*3][j*3:j*3+3])
                elem.extend(board[i*3+1][j*3:j*3+3])
                elem.extend(board[i*3+2][j*3:j*3+3])
                if not self.verfiy(elem):
                    return False
        return True 
        
    def verfiy(self,listNum):
        listNum = [x for x in listNum if x != '.']
        setNum = setNum = set(['1', '2', '3', '4', '5', '6', '7', '8', '9'])
        if len(listNum) == len(set(listNum)) and  set(listNum) <= setNum:
            return True
        return False