A.The time to find the value from HashMap with a Person key depends on the size of the map.
B.Deleting a Person key from a HashMap will delete all map entries for all keys of type Person.
C.Inserting a second Person object into a HashSet will cause the first Person object to be removed as a duplicate.
D.The time to determine whether a Person object is contained in a HashSet is constant and does NOT depend on the size of the map.

A.[1， 2， 3， 5]
B.[2， 1， 3， 5]
C.[2， 5， 3， 1]
D.[5， 3， 2， 1]
E.[1， 3， 5， 2]
F.Compilation fails.
G.An exception is thrown at runtime.

A.Compilation fails because the hashCode method is not overridden.
B.A HashSet could contain multiple Person objects with the same name.
C.All Person objects will have the same hash code because the hashCode  method is not overridden.
D.If a HashSet contains more than one Person object with name="Fred"， then removing another Person， also with name="Fred"， will remove them all.

A.The code runs with no output.
B.An exception is thrown at runtime.
C.Compilation fails because of an error in line 20.
D.Compilation fails because of an error in line 21.
E.Compilation fails because of an error in line 23.
F.Compilation fails because of an error in line 25.

A.3， 2， 1
B.1， 2， 3
C.Compilation fails.
D.The code runs with no output.
E.An exception is thrown at runtime.

A.A,B,C
B.B,C,A
C.Compilation fails.
D.The code runs with no output
E.An exception is thrown at runtime.

A.Arrays.sort（s）；
B.s = new TreeSet（s）；
C.Collections.sort（s）；
D.s = new SortedSet（s）；

A.2，1，0
B.2，1，1
C.3，2，1
D.3，2，2
E.Compilation fails.
F.An exception is thrown at runtime.

A.apple pear
B.banana pear
C.apple apple
D.apple banana
E.banana banana

A.list.add（"foo"）；
B.Object o = list；
C.String s = list.get（0）；
D.list = new ArrayList<String>（）；
E.list = new ArrayList<Object>（）；