Leetcode's "hash list": Valid Sudoku

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Title Requirements:

Determine if a Sudoku is valid, according To:sudoku puzzles-the Rules.

The Sudoku board could be partially filled, where empty cells is filled with the character ‘.‘ .

　　

A partially filled sudoku which is valid.

Note:
A Valid Sudoku board (partially filled) is not necessarily solvable. Only the filled cells need to be validated.

The solution of this problem is not quite ingenious, so the method used in the following procedure is brute force (violent cracking):

1 classSolution {2  Public:3     intChartoint (Charc)4     {5         CharStr[] = {'1','2','3','4','5','6','7','8','9'};6         intIntstr[] = {1,2,3,4,5,6,7,8,9};7          for(inti =0; I <9; i++)8         {9             if(c = =Str[i])Ten                 returnIntstr[i]; One         } A         return-1; -     } -      the     BOOLIsvalidsudoku (vector<vector<Char>>&Board) { -unordered_map<int,int> hashMap; -          for(inti =1; I <Ten; i++) -Hashmap[i] =0; +         //row by Row -          for(inti =0; I <9; i++) +         { A              for(intK =0; K <Ten; k++) atHASHMAP[K] =0; -              for(intj =0; J <9; J + +) -             { -                 intTMP =Chartoint (Board[i][j]); -                 if(tmp! =-1) -                 { inhashmap[tmp]++; -                     if(Hashmap[tmp] >1) to                         return false; +                 } -             } the         } *         //column by Column $          for(intj =0; J <9; J + +)Panax Notoginseng         { -              for(intK =1; K <Ten; k++) theHASHMAP[K] =0; +              for(inti =0; I <9; i++) A             { the                 intTMP =Chartoint (Board[i][j]); +                 if(tmp! =-1) -                 { $hashmap[tmp]++; $                     if(Hashmap[tmp] >1) -                         return false; -                 } the             } -         }Wuyi         //3*3 boxes by 3*3 boxes the          for(inti =0; I <9; i + =3) -         { Wu              for(intj =0; J <9; J + =3) -             { About                  for(intK =0; K <Ten; k++) $HASHMAP[K] =0; -                  for(intm = i; M < i +3; m++) -                      for(intn = j; N < J +3; n++) -                     { A                         intTMP =Chartoint (Board[m][n]); +                         if(tmp! =-1) the                         { -hashmap[tmp]++; $                             if(Hashmap[tmp] >1) the                                 return false; the                         } the                     } the             } -         } in          the         return true; the     } About};

Leetcode's "hash list": Valid Sudoku