36. 有效的数独

Posted 2021-03-05 yuhong1103

 1 class Solution 
 2 {
 3     int row[9][9] = {0};//某一行的某个数
 4     int col[9][9] = {0};//某一列的某个数
 5     int cell[3][3][9] = {0};//某一个九宫格中的某个数
 6 public:
 7     bool isValidSudoku(vector<vector<char>>& board) 
 8     {
 9         for(int i = 0;i < 9;i ++)
10         {
11             for(int j = 0;j < 9;j ++)
12             {
13                 if(board[i][j] != ‘.‘)
14                 {
15                     int val = board[i][j] - ‘1‘;
16                     if(!row[i][val] && !col[j][val] && !cell[i/3][j/3][val]) //全部为false才可以
17                     {
18                         row[i][val] = col[j][val] = cell[i/3][j/3][val] = true;
19                     }
20                     else return false;
21                 }
22             }
23         }
24         return true;
25     }
26 };