public SudokuBoard(String inputFile) throws IOException {
		BufferedReader in = null;
		
		try {
			in = new BufferedReader(new FileReader(inputFile));
			
			String line = null;
			
			//read in rows;
			for(int i = 0; i < 9;i++) {
				line = in.readLine();
				
				//read in a row
				for(int j = 0; j < 9;j++)
				{
					char c = line.charAt(j);
					if(c >= '1' & c <= '9') {
						b[i][j] = Character.getNumericValue(c);
						filledFields++;
					}
				}
			}
		} 
		finally {
			try{in.close();} catch(Exception e) {}
		}
	}