Sams Teach Yourself C in 21 Days

Working with C++ Classes and Objects 667

BD3

18: start_time.hours = 8;

19: start_time.minutes = 15;

20: start_time.seconds = 20;

21:

22: end_time.hours = 10;

23: end_time.minutes = 11;

24: end_time.seconds = 12;

25:

26: cout << “\nStart time: “;

27: print_time(start_time);

28: cout << “\n\nEnd time: “;

29: print_time(end_time);

30:

31: return 0;

32: }

33:

34: // Print a time structure in h:m:s format

35: //----------------------------------------

36: void print_time(struct time tm)

37: {

38: cout << tm.hours << “:” << tm.minutes << “:” << tm.seconds;

39: }

Start time: 8:15:20

End time: 10:11:12

Listing B3.1 presents a simple structure in lines 5–9 that holds the time in hours,

minutes, and seconds. In lines 15 and 16 two structures are declared as

start_timeandend_time. The data members of each of these time structures are initial-

ized in lines 18–24. The time values are then printed out in the function

display_time(), which is prototyped in line 11 and defined in lines 36–39.

Using Functions with Structures ..................................................................

Listing B3.1 uses a structure to create a time data element. There are a number of func-

tions you can associate with the time structure. You have already seen a simple function

calleddisplay_time(). The following are additional functions that can be directly asso-

ciated with the time structure:

add_hour()

add_minute()

add_second()

LISTINGB3.1 continued

OUTPUT

ANALYSIS

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