Chapter10_6e定义类.doc

Test Bank for Problem Solving with C+: The Object of Programming, 6/e Chapter 10 Defining ClassesTRUE/FALSE1. A struct variable is declared differently from a predefined type such as an int.ANSWER: FALSE2. Two different structure definitions may have the same member names.ANSWER: TRUE.3. A structure can only be passed to a function as a call-by-value parameterANSWER: FALSE4. A function may return a strucure.ANSWER: TRUE5. Different class may not have member functions with the same name.ANSWER: FALSE6. A class member function may be private.ANSWER: TRUE7. Class data members are almost always public.ANSWER: FALSE8. It is possible to have multiple private labels in a class definition.ANSWER: TRUE9. The assignment operator may not be used with objects of a class.ANSWER: FALSE10. All constructors for a class must be private.ANSWER: FALSEShort Answer1. The keyword _ defines a structure type definition.ANSWER: struct2. A structure definition ends with the closing brace and a _.ANSWER: semicolon3. A structure variable is a collection of smaller values called _ valuesANSWER: member4. When a structure contains another structure variable as one of its members, it is known as a _.ANSWER: hierarchical structure5. When several items (variables or variables and functions) are grouped together into a single package, that is known as _.ANSWER: (data) encapsulation6. The double colon (:) is known as the _ operator.ANSWER: scope resolution operator7. Who can access private members in a class?ANSWER: only other members of the class8. A member function that allows the user of the class to find out the value of a private data type is called a _.ANSWER: accessor function.9. A member function that allows the user of the class to change the value of a private data type is called a _.ANSWER: mutator function.10. If you have a class with a member function called display(ostream& out), that will send the values in the class to the parameter stream, and you need to call that function from within another member function, how would you call it to print the data to the screen? _ANSWER: display(cout);11. What can a constructor return? _ANSWER: nothing12. The name of a constructor is _ANSWER: the name of the class13. The constructor of a class that does not have any parameters is called a _ constructor.ANSWER: default14. In the following class constructor definition, the part of the header starting with a single colon is called the _.BankAccount:BankAccount(): balance(0), interest(0.0)ANSWER: initialization section15. A class in which modifications to the implementation appear to be invisible to the user of the class is known as _.ANSWER: an Abstract Data Type (ADT)16. A member function that gets called automatically when an object of the class is declared is called a _.ANSWER: constructorMultiple Choice1. In a structure definition, the identifiers declared in the braces are calleda. classesb. structsc. member namesd. variablesANSWER: C2. You specify an individual member of a struct by usinga. the assignment operatorb. an ampersandc. an underscored. The dot operatorANSWER: D3. To assign values to a structure variable, you use thea. equals operatorb. assignment operatorc. extraction operatord. less than operatorANSWER: B4. What is wrong witht the following structure definition?struct MyStructint size;float weight;a. Nothingb. Can not have mixed data types in a structurec. missing semicolond. Braces are not needed.ANSWER: C5. Given the following strucure definitions, what is the correct way to print the persons birth year?struct DateTypeint day;int month;int year;struct PersonTypeint age;float weight;DateType birthday;PersonType person;a. cout person.birthday.year;b. cout year;c. cout birthday.year;d. cout peson.year;ANSWER: A6. Given the following strucure definition, what is the correct way to initialize a variable called today?struct DateTypeint day;int month;int year;a. DateType today(1,1,2000);b. DateType today = (1,1,2000);c. DateType today = 1,1,2000);d. DateType today = 1,1,2000,0);ANSWER: C7. When defining a class, the class should be composed of the kind of values a vaiable of the class can contain, anda. member functions for that classb. the keyword privatec. other class definitionsd. nothing elseANSWER: A8. Which of the following is the correct function definition header for the getAge function which is a member of the Person class?a. int getAge();b. int getAge()c. int Person:getAge()d. int Person:getAge()ANSWER: D9. Given the following class definition and the following member function header, which is the correct way to output the private data?class Personpublic:void outputPerson(ostream& out);private:int age;float weight;int id;void outputPerson(ostream& out)/what goes here?a. out person.age person.weight person.id;b. out person;c. out age weight id;d. outputPerson(person);ANSWER: C10. Why do you want to usually make data members private in a class?a. so that no one can use the class.b. ensure data integrityc. provide data abstraction.d. provide information hiding.e. B and Df. B, C and DANSWER: F11. A member function of a class should be made privatea. alwaysb. only if it will never be usedc. if it will only be used by other members of the classd. never, it is illegal to make a member function private.ANSWER: C12. A member function that allow the user of the class to change the value in a data member is known asa. a mutator functionb. a mutationc. a manipulator functiond. an accessor functionANSWER: A13. A Member function that allows the user of the class to see the value in a data member is known asa. a mutator functionb. a mutationc. a manipulator functiond. an accessor functionANSWER: D14. If you design a class with private data members, and do not provide mutators and accessors, thena. The class cannot be usedb. The data can not be changed or viewed by anyone.c. None of the aboved. A and BANSWER: D15. A class member function that automatically initializes the data members of a class is called a. the init functionb. an operatorc. a constructord. a castANSWER: C16. If you have a class named myPersonClass, which of the following correctly declare a constructor in the class definition?a. myPersonClass:myPersonClass();b. myPersonClass();c. init();d. cast();ANSWER: B17. given the following class definition, how could you use the constructor to assign values to an object of this class?class CDAccountpublic:CDAccount();CDAccount(float interest, float newBalance);float getBalance();float getRate();void setRate(float interest);void setBalance(float newBalance);private:float balance, rate;and the following object declarationCDAccount myAccount;a. myAccount = CDAccount(float myRate, float myBalance);b. myAccount = CDAccount myRate, myBalance;c. myAccount = CDAccountmyRate, myBalance;d. myAccount = CDAccount(myRate, myBalance);ANSWER: D18. Given the following class definition, what is missing?class ItemClasspublic:ItemClass(int newSize, float newCost);int getSize();float getCost();void setSize(int newSize);void setCost(float newCost);private:int size;float cost;a. nothingb. a default constructorc. accessor functionsd. mutator functionsANSWER: B19. Given the following class definition, how would you declare an object of the class, so that the object automatically called the default constructor?class ItemClasspublic:ItemClass();ItemClass(int newSize, float newCost);int getSize();float getCost();void setSize(int newSize);void setCost(float newCost);private:int size;float cost;a. ItemClass() myItem;b. ItemClass myItem(1, 0.0);c. ItemClass myItem;d. ItemClass myItem();e. You can not do thisANSWER: C20. A data type consisting of data members and operations on those members which can be used by a programmer without knowing the implementation details of the data type is calleda. an abstract definition typeb. an available data typec. an abstract data typed. a primitive data typeANSWER: C21. Which part of the ADT tells the programmer using it how to use it?a. the implementationb. the interfacec. the abstractnessd. the scope resolutionANSWER: B22. If you are designing a class for an ADT, you can tell if the class is an ADT ifa. when you change the implementation of the class, none of the rest of the program needs to change.b. when you change the interface of the class, nothing else needs to change.c. you change the privte part and the rest of the program using the ADT does not compile.d. everything must be changed.ANSWER: A23. Developing an ADT means that the user of your class does not have to know the details about how the class is implemented. This is known asa. interfaceb. implementationc. testing and debuggingd. information hidingANSWER: D24. Given the following class, what would be the best declaration for a mutator function that allows the user of the class to change the age?class Winepublic:Wine();int getAge();float getCost();private:int age;float cost;a. int getAge(int newAge);b. Wine();c. void setAge();d. void setAge(int newAge);ANSWER: D25. Given the following class, what would be the best declaration for a constructor that would allow the user to initialize the object with an initial age and cost?class Winepublic:Wine();int getAge();float getCost();private:int age;float cost;a. int getAge(int newAge);b. Wine();c. Wine(int age);d.