Untitled

class Solution {
public:
    bool isValidSudoku(vector<vector<char>>& board) {
        vector<vector<int>> row(9,vector<int>(9,0)), col(9,vector<int>(9,0)), grid(9,vector<int>(9,0));
        for(int i=0;i<9;i++){
            for(int j=0;j<9;j++){
                if(board[i][j]!='.'){
                    int num=board[i][j]-'1';
                    int k= i/3*3 +j/3;
                    if(row[i][num] || col[num][j] || grid[k][num]) return false;
                    row[i][num]=col[num][j]=grid[k][num]=1;
                }
            }
        }
        return true;
    }
};