【LeetCode】Valid Sudoku

Valid Sudoku 

Total Accepted: 25228 Total Submissions: 92921 My Submissions Question Solution 
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.
Note:
A valid Sudoku board (partially filled) is not necessarily solvable. 
Only the filled cells need to be validated.
【解題思路】

判斷當前數據所在行和列有沒有相同的數。判斷9個小格子，每個格子中有沒有重複的數據。

Java AC

public class Solution {
    public boolean isValidSudoku(char[][] board) {
        int n = board.length;
        for(int i = 0; i < n; i++){
            for(int j = 0; j < n; j++){
                if(board[i][j] == '.'){
                    continue;
                }
                for(int k = 0; k < n; k++){
                	if (k == j) {
						continue;
					}
                    if(board[i][k] == board[i][j]){
//                    	System.out.println("1 "+i+" "+j );
                        return false;
                    }
                }
                for(int k = 0; k < n; k++){
                	if (k == i) {
						continue;
					}
                    if(board[k][j] == board[i][j]){
//                    	System.out.println("2 "+i+" "+j );
                        return false;
                    }
                }
                int rowStart = i / 3 * 3;
                int rowEnd = rowStart+3;
                int colStart = j / 3 * 3;
                int colEnd = colStart+3;
                for(int k = rowStart; k < rowEnd; k++){
                    for(int l = colStart; l < colEnd; l++){
                        if(k == i && l == j){
                            continue;
                        }
                        if(board[k][l] == board[i][j]){
//                        	System.out.println("3 "+i+" "+j );
                            return false;
                        }
                    }
                }
            }
        }
        return true;
    }
}

Python AC

class Solution:
    # @param board, a 9x9 2D array
    # @return a boolean
    def isValidSudoku(self, board):
        n = len(board)
        for i in xrange(n):
            for j in xrange(n):
                if board[i][j] == '.':
                    continue
                for k in range(n):
                    if k != i and board[k][j] == board[i][j]:
                        return False
                    if k != j and board[i][k] == board[i][j]:
                        return False
                rowStart = i / 3 * 3;
                rowEnd = rowStart + 3
                colStart = j / 3 * 3
                colEnd = colStart + 3
                for k in xrange(rowStart, rowEnd, 1):
                    for l in xrange(colStart, colEnd, 1):
                        if k == i and l == j:
                            continue
                        if board[k][l] == board[i][j]:
                            return False
        return True