@Override
	/**
	 * \𕶎\ŕԂ܂B
	 */
	public String toString() {
		String clrl = System.getProperty("line.separator");
		String str = "";
		
		str += super.toString();
		for ( int row=0; row<rows; ++row ) {
			String line = "";
			for ( int col=0; col<columns; ++col ) {
				line += getLetters()[row*columns + col];
			}
			str += clrl + line;
		}
		
		return str;
	}