[LeetCode]Valid Sudoku

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.

思考：参考这里。

class Solution {
public:
    bool isValidSudoku(vector<vector<char> > &board) {
        vector<vector<bool> > rows(9,vector<bool>(9,false));
        vector<vector<bool> > cols(9,vector<bool>(9,false));
        vector<vector<bool> > blocks(9,vector<bool>(9,false));
        for(int i=0;i<9;i++)
        {
            for(int j=0;j<9;j++)
            {
                if(board[i][j]=='.') continue;
                int c=board[i][j]-'1';
                if(rows[i][c]||cols[j][c]||blocks[i-i%3+j/3][c]) return false;
                rows[i][c]=cols[j][c]=blocks[i-i%3+j/3][c]=true;
            }
        }
        return true;
    }
};