C语言编程
关于实足年龄的问题：输入学生的生日和当前生日，输出该学生的实足年龄。
[解决办法]
print today - birthday;
[解决办法]
difftime
Finds the difference between two times.

double difftime( time_t timer1, time_t timer0 );

Routine Required Header Compatibility
difftime <time.h> ANSI, Win 95, Win NT


For additional compatibility information, see Compatibility in the Introduction.

Libraries

LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version


Return Value

difftime returns the elapsed time in seconds, from timer0 to timer1. The value returned is a double-precision floating-point number.

Parameters

timer1

Ending time

timer0

Beginning time

Remarks

The difftime function computes the difference between the two supplied time values timer0 and timer1.

Example

/* DIFFTIME.C: This program calculates the amount of time
* needed to do a floating-point multiply 10 million times.
*/

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

void main( void )
{
time_t start, finish;
long loop;
double result, elapsed_time;

printf( "Multiplying 2 floating point numbers 10 million times...\n" );

time( &start );
for( loop = 0; loop < 10000000; loop++ )
result = 3.63 * 5.27;
time( &finish );

elapsed_time = difftime( finish, start );
printf( "\nProgram takes %6.0f seconds.\n", elapsed_time );
}


Output

Multiplying 2 floats 10 million times...

Program takes 2 seconds.


Floating-Point Support Routines
[解决办法]
Time Management Routines

See Also time