int rand( void );#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
#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
//即每次运行产生的随机数不同。
int rand_number = rand();//产生一个随机数:0~RAND_MAX
rand_number = rand_number*high/RAND_MAX+low//产生low~high之间的一
//个随机数。
用这个公式就可以。