include <stdio.h>

int main()
{
int magic;
int guess;
int xuan;
srand(time(NULL));
magic=rand(%d)/6+1;
printf("%d,magic");
printf ("请猜出股子数");
do
{
scanf("%d",&guess);
if(guess<magic);
printf ("猜小了");
else
if(guess>magic);
printf ("猜大了");
else
printf ("恭喜你，猜对了");
} while(magic!=guess);
return 0;
}

加 stdlib.h和time.h