Sudoku

public class Sudoku {
 
	static int[][] board;
 
	public static void main(String[] arg) {
		String[] init = new String[9];
		init[0] = new String("060310050");
		init[1] = new String("000406000");
		init[2] = new String("003000700");
		init[3] = new String("030805090");
		init[4] = new String("102090304");
		init[5] = new String("070103060");
		init[6] = new String("006000900");
		init[7] = new String("000502000");
		init[8] = new String("040080020");
 
		board = new int[9][9];
		for (int i=0;i<9;i++) {
			for (int j=0;j<9;j++) {
				board[i][j] = Integer.parseInt(init[i].substring(j, j+1));
			}
		}
		printBoard();
		solveNext(-1,-1);
 
//		System.out.println("i="+i+", j="+j);
	}
 
	private static boolean solveNext(int i, int j) {
		boolean result = false;
		j = (j+1)%9;
		i = i+(j==0?1:0);
		if (i==9) {
			result = true;
			printBoard();
		} else {
			if (board[i][j] != 0) {
				result = solveNext(i,j);
			} else {
				for (int val = 1; val <= 9 && !result; ++val) {
					if (cellValid(i,j, val)) {
						board[i][j] = val;
						result = solveNext(i,j);
					}
				}
				board[i][j] = 0;
			}
		}
		return result;
	}
 
	private static boolean cellValid(int i, int j, int val) {
		for (int r=0;r<9;r++)
			for (int c=0;c<9;c++)
				if ((r!=i||c!=j)&&
					board[r][c]!=0&&
					board[r][c]==val&&
					(r==i||c==j||(i/3==r/3&&j/3==c/3))) {
					return false;
				}
		return true;
	}
 
	public static void printBoard() {
		for (int i=0;i<9;i++) {
			for (int j=0;j<9;j++) {
				System.out.print(board[i][j]);
			}
			System.out.println();
		}
		System.out.println("---------");
	}
}