36_ValidSudoku

bool isValidSudoku(vector<vector<char>>& board) {
        unordered_set<int>       
        map,map2,map3,map4,map5,map6,map7,map8,map9;
        for(int i=0; i<9; i++){
            for(int j=0; j<9; j++){
                if(board[i][j]=='.')
                    continue;
                if(map.count(board[i][j]))
                    return false;
                else
                    map.insert(board[i][j]);
            }
            map.clear();
        }
        map.clear();
        for(int i=0; i<9; i++){
            for(int j=0; j<9; j++){
                if(board[j][i]=='.')
                    continue;
                if(map.count(board[j][i]))
                    return false;
                else
                    map.insert(board[j][i]);
            }
            map.clear();
        }
        map.clear();
        for(int i=0; i<9; i++){
            for(int j=0; j<9; j++){
                if(i<=2 && j<=2){
                    if(board[i][j]=='.')
                        continue;
                    if(map.count(board[i][j]))
                        return false;
                    else
                        map.insert(board[i][j]);
                }
                if(i<=2 && (j>2 && j<6)){
                    if(board[i][j]=='.')
                        continue;
                    if(map2.count(board[i][j]))
                        return false;
                    else
                        map2.insert(board[i][j]);
                }
                if(i<=2 && (j>5 && j<9)){
                    if(board[i][j]=='.')
                        continue;
                    if(map3.count(board[i][j]))
                        return false;
                    else
                        map3.insert(board[i][j]);
                }
                if((i>2 && i<6) && j<=2){
                    if(board[i][j]=='.')
                        continue;
                    if(map4.count(board[i][j]))
                        return false;
                    else
                        map4.insert(board[i][j]);
                }
                if((i>2 && i<6) && (j>2 && j<6)){
                    if(board[i][j]=='.')
                        continue;
                    if(map5.count(board[i][j]))
                        return false;
                    else
                        map5.insert(board[i][j]);
                }
                if((i>2 && i<6) && (j>5 && j<9)){
                    if(board[i][j]=='.')
                        continue;
                    if(map6.count(board[i][j]))
                        return false;
                    else
                        map6.insert(board[i][j]);
                }
                if((i>5 && i<9) && j<=2){
                    if(board[i][j]=='.')
                        continue;
                    if(map7.count(board[i][j]))
                        return false;
                    else
                        map7.insert(board[i][j]);
                }
                if((i>5 && i<9) && (j>2 && j<6)){
                    if(board[i][j]=='.')
                        continue;
                    if(map8.count(board[i][j]))
                        return false;
                    else
                        map8.insert(board[i][j]);
                }
                if((i>5 && i<9) && (j>5 && j<9)){
                    if(board[i][j]=='.')
                        continue;
                    if(map9.count(board[i][j]))
                        return false;
                    else
                        map9.insert(board[i][j]);
                }
            }
        }
        map2.clear(); map3.clear(); map4.clear(); map5.clear();
        map6.clear(); map7.clear(); map8.clear(); map9.clear();
        return true;
    }