private String[] getFirstSubtractionSignAndBreak(String contents) {
		for (int i = 0; i < contents.length() - 1; i++) {
			if (contents.charAt(i + 1) == '-' && contents.charAt(i) != 'E') return new String[] {contents.substring(0, i + 1), contents.substring(i + 2)};
		}
		return null;
	}