ArrayList list = new ArrayList(); int a;//个 int b;//十 int c;//百 int d;//千 for (int i = 10000; i >0;i--) { a= i%10; b = i%100/10; c = i%1000/100; d = i%10000/1000; if (a-b-c-d>0){ System.out.println(i); list.add(i); } } System.out.println("个数:"+ list.size());