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public class Demo{ public static void main(String[] args){ List al = new ArrayList(); al.add(“1”); al.add(“2”); al.add(“2”); al.add(“3”); System.out.println(al); } } 上述程序执行后的输出是哪项?()
- A、 [1,2,3]
- B、 [1,2,2,3]
- C、 [1,2,3,3]
- D、 [2,1,3,2]
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更多 “ public class Demo{ public static void main(String[] args){ List al = new ArrayList(); al.add(“1”); al.add(“2”); al.add(“2”); al.add(“3”); System.out.println(al); } } 上述程序执行后的输出是哪项?() A、 [1,2,3]B、 [1,2,2,3]C、 [1,2,3,3]D、 [2,1,3,2]” 相关考题
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考题
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