Sams Teach Yourself C in 21 Days

Advanced Program Control 319

13

49: {

50: puts(“\nInvalid choice, try again.”);

51: delay();

52: }

53: }

54: return 0;

55: }

56:

57: /* Displays a menu and inputs user’s selection. */

58: int menu(void)

59: {

60: int reply;

61:

62: puts(“\nEnter 1 for task A.”);

63: puts(“Enter 2 for task B.”);

64: puts(“Enter 3 for task C.”);

65: puts(“Enter 4 for task D.”);

66: puts(“Enter 5 to exit program.”);

67:

68: scanf(“%d”, &reply);

69:

70: return reply;

71: }

72:

73: void delay( void )

74: {

75: long x;

76: for ( x = 0; x < DELAY; x++ )

77: ;

78: }

Enter 1 for task A.

Enter 2 for task B.

Enter 3 for task C.

Enter 4 for task D.

Enter 5 to exit program.

1

Executing task A.

Enter 1 for task A.

Enter 2 for task B.

Enter 3 for task C.

Enter 4 for task D.

Enter 5 to exit program.

6

LISTING13.4 continued

INPUT/

OUTPUT

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