随机数100个不重复

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//方式1
		List<Integer> a = new ArrayList<Integer>();
		
		
		for (int i = 0; i < 1000; i++) {
			a.add(new Random().nextInt());
		}
		int num = 0;
		
		Map<Integer, String> map = new HashMap<Integer, String>();
		for (int i = 0; i <a.size(); i++) {
			if(!map.containsKey(a.get(i))) {
				//System.out.println(a.get(i));
				map.put(a.get(i), null);
				num++;
				
				if(num==100) {
					break;
					
				}
			}
			
			
		}
		
		
		for (Map.Entry<Integer, String> integer : map.entrySet()) {
			System.out.println(integer.getKey());
		}
		
		//方式2
		
		Set<Integer> set = new TreeSet<>();
		int r = 0;
		for (int i = 0; i < 1000; i++) {
			 r = (int) (Math.random()*100);
			  //System.out.println(r);
			set.add(r);
		}
		
		set.forEach(s->{
			
			System.out.println(s);
		});