public void setColor(int r, int c, char clr){
		if(r >= size || c >= size || r < 0 || c < 0){
			System.err.println("Invalid dimentions (" + r + "," + c + ") for size " + size);
			System.exit(0);
		}
		
		if(clr != '.')
			puzzle[r][c].color(clr);
		else
			puzzle[r][c].uncolor();
	}