public static ClauseSet get(File file) {
		ClauseSet clauseSet = new ClauseSet();
		Scanner scan = null;
		try {
			scan = new Scanner(file);
			while (scan.nextLine().startsWith("c")) {/* skip commments */
			}
			Clause clause = new Clause();
			while (scan.hasNextInt()) {
				int var = scan.nextInt();
				if (var == 0) {
					clauseSet.add(clause);
					clause = new Clause();
				} else {
					clause.add(var);
				}
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (NoSuchElementException e) {
			System.out.println("No DIMACS format");
			return null;
		} finally {
			scan.close();
		}

		return clauseSet;
	}