我今天接受了采访,得到了以下Java代码:
public class Question_6 {
public static void main(String[] args){
Map<Integer,String> map1 = new HashMap<Integer,String>();
map1.put(new Integer(1),"001a");
map1.put(new Integer(1),"001b");
map1.put(new Integer(2),"002");
System.out.println(map1.size());
Map<MyInt,String> map2 = new HashMap<MyInt,String>();
map2.put(new MyInt(1),"001a");
map2.put(new MyInt(1),"001b");
map2.put(new MyInt(2),"002");
System.out.println(map2.size());
}
}
public class MyInt {
int i;
public MyInt(int i) {
this.i = i;
}
}
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问题是:
什么将打印到控制台?
建议解决问题的方法.
我现在知道第一个问题的答案是:
2
3
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但我不知道为什么?有什么问题MyInt?