试题详情
单项选择题 import java.util.*;  class KeyMaster {  public int i;  public KeyMaster(int i) { this.i = i; }  public boolean equals(Object o) { return i == ((KeyMaster)o).i; }  public int hashCode() { return i; }  }  public class MapIt {  public static void main(String[] args) {  Set set = new HashSet();  KeyMaster k1 = new KeyMaster(1);  KeyMaster k2 = new KeyMaster(2);  set.add(k1); set.add(k1);  set.add(k2); set.add(k2);  System.out.print(set.size() + “:”);  k2.i = 1;  System.out.print(set.size() + “:”);  set.remove(k1);  System.out.print(set.size() + “:”);  set.remove(k2);  System.out.print(set.size()); }  }  What is the result?() 

A、 4:4:2:2

B、 4:4:3:2

C、 2:2:1:0

D、 2:2:0:0

E、 2:1:0:0

F、 2:2:1:1

G、 4:3:2:1

  • F
  • 关注下方微信公众号,在线模考后查看

热门试题