判断一个 9x9 的数独是否有效。只需要根据以下规则，验证已经填入的数字是否有效即可。数字 1-9 在每一行只能出现一次。
数字 1-9 在每一列只能出现一次。
数字 1-9 在每一个以粗实线分隔的 3x3 宫内只能出现一次。上图是一个部分填充的有效的数独。数独部分空格内已填入了数字，空白格用 '.' 表示。示例 1:输入:
[["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"]
]
输出: true
示例 2:输入:
[["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"]
]
输出: false
解释: 除了第一行的第一个数字从 5 改为 8 以外，空格内其他数字均与 示例1 相同。但由于位于左上角的 3x3 宫内有两个 8 存在, 因此这个数独是无效的。
说明:一个有效的数独（部分已被填充）不一定是可解的。
只需要根据以上规则，验证已经填入的数字是否有效即可。
给定数独序列只包含数字 1-9 和字符 '.' 。
给定数独永远是 9x9 形式的。

class Solution {
public:bool isValidBlock(vector<vector<char>>& board,int x,int y){set<int> test;for(int i = x;i<x+3;++i){for(int j = y;j < y+3;++j){if(board[i][j] == '.'){continue;}if(!(board[i][j] <= '9' && board[i][j] >= '1')){return false;}if(board[i][j] <= '9' && board[i][j] >= '1'){if(test.find(board[i][j]-'0')==test.end()){test.insert(board[i][j]-'0');}else{return false;}}}}return true;}bool isValidRow(vector<vector<char>>& board,int row){set<int> test;for(int i = 0;i < 9;++i){if(board[row][i] == '.'){continue;}if(!(board[row][i] >= '1' && board[row][i] <= '9')){return false;}if(test.find(board[row][i]-'0')==test.end()){test.insert(board[row][i]-'0');}else{return false;}}return true;}bool isValidColum(vector<vector<char>>& board,int colum){set<char> test;for(int i = 0;i<9;++i){if(board[i][colum] == '.'){continue;}if(!(board[i][colum] <= '9' && board[i][colum] >= '1')){return false;}if(test.find(board[i][colum]-'0')==test.end()){test.insert(board[i][colum]-'0');}else{return false;}}return true;}bool isValidSudoku(vector<vector<char>>& board) {/*check row & colum*/for(int i = 0; i < 9; ++i){if(!isValidRow(board,i)||!isValidColum(board,i)){cout<<i<<endl;return false;}}/*check block*/for(int i = 0;i < 9; i += 3){for(int j = 0;j < 9; j += 3){if(!isValidBlock(board,i,j)){cout<<i<<j<<endl;return false;}}}return true;}
};