int DateAndTime::getMinute() {
return minute;
} // end function getMinute int DateAndTime::getSecond() {
return second;
} // end function getSecond
void DateAndTime::printStandard() {
cout << ( ( hour % 12 == 0 ) ? 12 : hour % 12 ) << ':' << ( minute < 10 ? \ : \ ) << minute << ':' << ( second < 10 ? \ : \ ) << second << ( hour < 12 ? \ : \ )
<< month << '-' << day << '-' << year << endl; } // end function printStandard void DateAndTime::printUniversal() {
cout << ( hour < 10 ? \ : \ ) << hour << ':' << ( minute < 10 ? \ : \ ) << minute << ':' << ( second < 10 ? \ : \ ) << second << \ << month << '-' << day << '-' << year << endl; } // end function printUniversal bool DateAndTime::leapYear() {
if ( year % 400 == 0 || ( year % 4 == 0 && year % 100 != 0 ) ) return true; // is a leap year else
return false; // is not a leap year } // end function leapYear int DateAndTime::monthDays() {
const int days[ 12 ]={31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; return ( month == 2 && leapYear() ) ? 29 : days[ ( month - 1 ) ]; } // end function monthDays 测试函数：
#include
#include \ // include definitions of class DateAndTime int main() {
const int MAXTICKS = 30;
DateAndTime d( 12, 31, 2004, 23, 59, 57 ); // instantiates object d
// of class DateAndTime for ( int ticks = 1; ticks <= MAXTICKS; ticks++ ) {
cout << \;
d.printUniversal(); // invokes function printUniversal cout << \;
d.printStandard(); // invokes function printStandard d.tick(); // invokes function tick } // end for cout << endl; return 0; } // end main 9.10 类定义：
#ifndef TIME_H #define TIME_H class Time {
public:
Time( int = 0, int = 0, int = 0 ); // default constructor bool setTime( int, int, int ); // set hour, minute, second bool setHour( int ); // set hour
bool setMinute( int ); // set minute bool setSecond( int ); // set second int getHour(); // get hour
int getMinute(); // get minute int getSecond(); // get second
void printUniversal(); // print universal time void printStandard(); // print standard time private:
int hour; // 0-23
int minute; // 0-59 int second; // 0-59 }; // end class Time #endif
类成员函数：
#include
#include \ // include definition of class Time Time::Time( int hr, int min, int sec ) {
setTime( hr, min, sec ); } // end Time constructor
bool Time::setTime( int h, int m, int s ) {
bool hourValid = setHour( h ); // invokes function setHour bool minuteValid = setMinute( m ); // invokes function setMinute bool secondValid = setSecond( s ); // invokes function setSecond return hourValid && minuteValid && secondValid; } // end function setTime bool Time::setHour( int hr ) {
if ( hr >= 0 && hr < 24 ) {
hour = hr;
return true; // hour is valid } // end if else {
hour = 0;
return false; // hour is invalid } // end else
} // end function setHour
bool Time::setMinute( int min ) {
if ( min >= 0 && min < 60 ) {
minute = min;
return true; // minute is valid } // end if else {
minute = 0;
return false; // minute is invalid } // end else
} // end function setMinute
bool Time::setSecond( int sec ) {
if ( sec >= 0 && sec < 60 ) {
second = sec;
return true; // second is valid } // end if else {
second = 0;
return false; // second is invalid } // end else
} // end function setSecond // return hour value int Time::getHour() {
return hour;
} // end function getHour // return minute value int Time::getMinute() {
return minute;
} // end function getMinute // return second value int Time::getSecond() {
return second;
} // end function getSecond void Time::printUniversal() {
cout << ( hour < 10 ? \ : \ ) << hour << ':' << ( minute < 10 ? \ : \ ) << minute << ':' << ( second < 10 ? \ : \ ) << second; } // end function printUniversal void Time::printStandard() {
cout << ( ( hour % 12 == 0 ) ? 12 : hour % 12 ) << ':' << ( minute < 10 ? \: \ ) << minute << ':' << ( second < 10 ? \: \ ) << second << ( hour < 12 ? \ : \ ); } // end function printStandard 测试函数：
#include
#include \ // include definition of class Time int getMenuChoice(); // prototype int main() {
Time time; // the Time object int choice = getMenuChoice(); int hours; int minutes;
int seconds;
while ( choice != 4 ) {
switch ( choice ) {
case 1: // set hour
cout << \; cin >> hours;
if ( !time.setHour( hours ) )
cout << \ << endl; break;
case 2: // set minute
cout << \; cin >> minutes;
if ( !time.setMinute( minutes ) )
cout << \ << endl; break;
case 3: // set seconds
cout << \; cin >> seconds;
if ( !time.setSecond( seconds ) )
cout << \ << endl; break; } // end switch
cout << \ << time.getHour() << \
<< time.getMinute() << \Second: \ << time.getSecond() << endl; cout << \; time.printUniversal();
cout << \; time.printStandard(); cout << endl;
choice = getMenuChoice(); } // end while } // end main
// prints a menu and returns a value corresponding to the menu choice int getMenuChoice() {
int choice;
cout << \ << \ << endl; cin >> choice; return choice;
} // end function getMenuChoice 9.11
《C++大学教程第五版》课后习题答案(第3、9章)
