題目描述

判斷一個 9x9 的數(shù)獨是否有效。只需要根據(jù)以下規(guī)則，驗證已經(jīng)填入的數(shù)字是否有效即可。

數(shù)字 1-9 在每一行只能出現(xiàn)一次。
數(shù)字 1-9 在每一列只能出現(xiàn)一次。
數(shù)字 1-9 在每一個以粗實線分隔的 3x3 宮內(nèi)只能出現(xiàn)一次。

數(shù)獨部分空格內(nèi)已填入了數(shù)字，空白格用 '.' 表示。

示例 1:

輸入:
[
["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"]
]
輸出: true
示例 2:

輸入:
[
["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"]
]
輸出: false
解釋: 除了第一行的第一個數(shù)字從 5 改為 8 以外，空格內(nèi)其他數(shù)字均與 示例1 相同。
但由于位于左上角的 3x3 宮內(nèi)有兩個 8 存在, 因此這個數(shù)獨是無效的。
說明:

一個有效的數(shù)獨（部分已被填充）不一定是可解的。
只需要根據(jù)以上規(guī)則，驗證已經(jīng)填入的數(shù)字是否有效即可。
給定數(shù)獨序列只包含數(shù)字 1-9 和字符 '.' 。
給定數(shù)獨永遠(yuǎn)是 9x9 形式的。

知識點

數(shù)組

Qiang的思路

class Solution:
    def getResult(self, line: List[str]) -> bool:
        flag=[0 for i in range(10)]
        for c in line:
            if c=='.':
                continue
            if flag[int(c)]==1:
                return False
            flag[int(c)]=1
        return True
    
    def isValidSudoku(self, board: List[List[str]]) -> bool:
        for i in range(9):
            line=[a for a in board[i]]
            if self.getResult(line)==False:
                return False
        for i in range(9):
            line=[b for a in board for b in a[i]]
            if self.getResult(line)==False:
                return False
        for i in range(3):
            for j in range(3):
                line=[b for a in board[i*3:(i+1)*3] for b in a[j*3:(j+1)*3]]
                if self.getResult(line)==False:
                    return False
        return True

作者原創(chuàng)，如需轉(zhuǎn)載及其他問題請郵箱聯(lián)系：lwqiang_chn@163.com。
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