/*
		 * set遍歷第一種方法
		 */
		//如果set定義了型別
		Set<String> setstr = new HashSet<String>();
		for(String s: setstr) {
			System.out.println("固定型別的set: " + s);
		}
		//set為object型別
		Set<Object> set = new HashSet<Object>();
		for(Object obj: set) {
			if (obj instanceof Character) {
				char chr = (Character)obj;
				System.out.println("for: "+chr);
			}
		}
		
		/*
		 * 第二種方法
		 */
		Iterator<Object> i = set.iterator();
		while(i.hasNext()) {
			System.out.println("i.next(): "+i.next());
		}