} // end function setDate
void Date::setDay( int d ) {
if ( month == 2 && leapYear() )
day = ( d <= 29 && d >= 1 ) ? d : 1; else
day = ( d <= monthDays() && d >= 1 ) ? d : 1; } // end function setDay
void Date::setMonth( int m ) {
month = m <= 12 && m >= 1 ? m : 1; // sets month } // end function setMonth
void Date::setYear( int y ) {
year = y >= 1900 ? y : 1900; // sets year } // end function setYear
int Date::getDay() {
return day;
} // end function getDay
int Date::getMonth() {
return month;
} // end function getMonth
int Date::getYear() {
return year;
} // end function getYear
void Date::print() {
cout << month << '-' << day << '-' << year << '\\n'; // outputs date } // end function print
void Date::nextDay() {
setDay( day + 1 ); // increments day by 1
if ( day == 1 ) {
setMonth( month + 1 ); // increments month by 1
if ( month == 1 )
setYear( year + 1 ); // increments year by 1 } // end if statement } // end function nextDay
bool Date::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 Date::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 Date
int main() {
const int MAXDAYS = 16;
Date d( 12, 24, 2004 ); // instantiate object d of class Date
// output Date object d's value
for ( int loop = 1; loop <= MAXDAYS; ++loop ) {
d.print(); // invokes function print
d.nextDay(); // invokes function next day } // end for
cout << endl;
return 0; } // end main 9.09 类定义：
#ifndef DATEANDTIME_H #define DATEANDTIME_H class DateAndTime {
public:
DateAndTime( int = 1, int = 1, int = 1900,int = 0, int = 0, int = 0 );
// default constructor
void setDate( int, int, int ); // set month, day, year void setMonth( int ); // set month void setDay( int ); // set day void setYear( int ); // set year void nextDay(); // next day
void setTime( int, int, int ); // set hour, minute, second void setHour( int ); // set hour
void setMinute( int ); // set minute void setSecond( int ); // set second void tick(); // tick function int getMonth(); // get month int getDay(); // get day int getYear(); // get year int getHour(); // get hour
int getMinute(); // get minute int getSecond(); // get second
void printStandard(); // print standard time void printUniversal(); // print universal time private:
int month; // 1-12
int day; // 1-31 (except February(leap year), April, June, Sept, Nov) int year; // 1900+
int hour; // 0-23 (24 hour clock format) int minute; // 0-59 int second; // 0-59
bool leapYear(); // leap year
int monthDays(); // days in month }; // end class DateAndTime #endif
类成员函数：
#include
#include \ // include definition of class DateAndTime DateAndTime::DateAndTime(
int m, int d, int y, int hr, int min, int sec ) {
setDate( m, d, y ); // sets date
setTime( hr, min, sec ); // sets time } // end DateAndTime constructor
void DateAndTime::setDate( int mo, int dy, int yr ) {
setMonth( mo ); // invokes function setMonth setDay( dy ); // invokes function setday setYear( yr ); // invokes function setYear } // end function setDate
void DateAndTime::setDay( int d ) {
if ( month == 2 && leapYear() )
day = ( d <= 29 && d >= 1 ) ? d : 1; else
day = ( d <= monthDays() && d >= 1 ) ? d : 1; } // end function setDay
void DateAndTime::setMonth( int m ) {
month = m <= 12 && m >= 1 ? m : 1; // sets month } // end function setMonth
void DateAndTime::setYear( int y ) {
year = y >= 1900 ? y : 1900; // sets year } // end function setYear void DateAndTime::nextDay() {
setDay( day + 1 ); // increments day by 1 if ( day == 1 ) {
setMonth( month + 1 ); // increments month by 1 if ( month == 1 )
setYear( year + 1 ); // increments year by 1 } // end if statement } //end function nextDay
void DateAndTime::setTime( int hr, int min, int sec ) {
setHour( hr ); // invokes function setHour
setMinute( min ); // invokes function setMinute setSecond( sec ); // invokes function setSecond
} // end function setTime
void DateAndTime::setHour( int h ) {
hour = ( h >= 0 && h < 24 ) ? h : 0; // sets hour } // end function setHour
void DateAndTime::setMinute( int m ) {
minute = ( m >= 0 && m < 60 ) ? m : 0; // sets minute } // end function setMinute
void DateAndTime::setSecond( int s ) {
second = ( s >= 0 && s < 60 ) ? s : 0; // sets second } // end function setSecond void DateAndTime::tick() {
setSecond( second + 1 ); // increments second by 1 if ( second == 0 ) {
setMinute( minute + 1 ); // increments minute by 1 if ( minute == 0 ) {
setHour( hour + 1 ); // increments hour by 1 if ( hour == 0 )
nextDay(); // increments day by 1 } // end if } // end if
} // end function tick
int DateAndTime::getDay() {
return day;
} // end function getDay int DateAndTime::getMonth() {
return month;
} // end function getMonth int DateAndTime::getYear() {
return year;
} // end function getYear int DateAndTime::getHour() {
return hour;
} // end function getHour
《C++大学教程第五版》课后习题答案(第3、9章)
