[LeetCode]题解（python）：036-Valid Sudoku

---

题目来源

https://leetcode.com/problems/valid-sudoku/

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

---

题意分析
Input: a list means the sudoku with each element in the list is a str

Output:True or False

Conditions:看已有的数字是否满足数独的条件（每行、列、小九方格不能一样的数字）

---

题目思路

此题是判断已有的矩阵块是否为有效的数独组，分别遍历每一行，每一列，每一个小九方格即可，注意下标范围

---

AC代码（Python）

---

_author_ = "YE"
# -*- coding:utf-8 -*-
class Solution(object):
    def verifyRow(self, board):
        for i in range(9):
            L = []
            for j in range(9):
                if board[i][j] == '.':
                    continue
                elif board[i][j] in L:
                    return False
                else:
                    L.append(board[i][j])
        return True

    def verifyColumn(self, board):
        for j in range(9):
            L = []
            for i in range(9):
                if board[i][j] == '.':
                    continue
                elif board[i][j] in L:
                    return False
                else:
                    L.append(board[i][j])
        return True

    def verifySquare(self, board):
        for i in range(3):
            for j in range(3):
                L = []
                for k in range(3):
                    for x in range(3):
                        if board[3 * i + k][3 * j + x] == '.':
                            continue
                        elif board[3 * i + k][3 * j + x] in L:
                            return False
                        else:
                            L.append(board[3 * i + k][3 * j + x])
        return True

    def isValidSudoku(self, board):
        """
        :type board: List[List[str]]
        :rtype: bool
        """
        numbers = len(board[0])
        print(numbers)

        # print('row:',self.verifyRow(board))
        if not self.verifyRow(board):
            return False
        # print('column:',self.verifyColumn(board))
        if not self.verifyColumn(board):
            return False
        # print('square:',self.verifySquare(board))
        if not self.verifySquare(board):
            return False

        return True

#test code
s = Solution()
board = [".87654321","2........","3........","4........","5........","6........","7........","8........","9........"]
print(s.isValidSudoku(board))