问题描写叙述：

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.

代码：

public class Valid_Sudoku {  //java

	public boolean isValidSudoku(char[][] board) {
        
		int size = 9;
		int [] member = new int[size];   //record if is occur; 
		
		//valid row
		for(int i = 0; i < 9; i++){
			
			for(int k = 0; k < 9; k++)
				member[k] = 0;
			for(int j = 0; j < 9; j++){
				if(board[i][j] == ‘.‘)
					continue;
				int pos = board[i][j]-‘0‘;
				if(member[pos-1] == 1)
					return false;
				else member[pos-1] = 1;
			}
		}
		
		//valid col
		for(int i = 0; i < 9; i++){
			for(int k = 0; k < 9; k++)
				member[k] = 0;
			for(int j = 0; j < 9; j++){
				if(board[j][i] == ‘.‘)
					continue;
				int pos = board[j][i]-‘0‘;
				if(member[pos-1] == 1)
					return false;
				else member[pos-1] = 1;
			}
		}
		
		//valid cube
		for(int ibegin = 0; ibegin < 9; ibegin = ibegin+3){
			for(int jbegin = 0; jbegin < 9; jbegin = jbegin+3){
				for(int k = 0; k < 9; k++)
					member[k] = 0;
				for(int i = ibegin; i < ibegin+3; i++){
					for(int j = jbegin; j < jbegin+3; j++){
						if(board[i][j] == ‘.‘)
							continue;
						int pos = board[i][j]-‘0‘;
						if(member[pos-1] == 1)
							return false;
						else member[pos-1] = 1;
					}
				}
			}
		}
		return true;
    }
	
	public static void main(String [] args){
		String[] boardStr = {"......5..",
							 ".........",
							 ".........",
							 "93..2.4..",
							 "..7...3..",
							 ".........",
							 "...34....",
							 ".....3...",
							 ".....52.."};
		char [][] board = new char [9][9];
		for(int i =0; i< boardStr.length; i++){
			for(int j = 0; j<boardStr[i].length(); j++){
				board[i][j] = boardStr[i].charAt(j);
			}
		}
		
		Valid_Sudoku vs = new Valid_Sudoku();
		System.out.println(vs.isValidSudoku(board));
	}
}