照书抄的：）看不懂，好深奥呀
#define NULL 0
#define ALLOCSIZE1000
char allocbuf[ALLOCSIZE];
char *allocp=allocbuf;
char *alloc(int n)
{if(allocp+n<=allocbuf+ALLOCSIZE)
{allocp+=n;
return(allocp_n);
}
else
return(null);
}
free(char * p)
{if(p>=allocbuf&&p>allocbuf+ALLOCSIZE)
allocp=p;
}
