change the random number everytime

rand

Generates a pseudorandom number.

int rand( void );

Routine	Required Header	Compatibility
rand	<stdlib.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

rand returns a pseudorandom number, as described above. There is no error return.

Remarks

The rand function returns a pseudorandom integer in the range 0 toRAND_MAX. Use the srand function to seed the pseudorandom-number generator before callingrand.

Example

/* RAND.C: This program seeds the random-number generator
 * with the time, then displays 10 random integers.
 */

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

void main( void )
{
   int i;

   /* Seed the random-number generator with current time so that
    * the numbers will be different every time we run.
    */
   srand( (unsigned)time( NULL ) );

   /* Display 10 numbers. */
   for( i = 0;   i < 10;i++ )
      printf( "  %6d\n", rand() );
}

Output

    6929
    8026
   21987
   30734
   20587
    6699
   22034
   25051
    7988
   10104